JP7600721B2 - Computers and computer programs - Google Patents

Description

The present invention relates to a computer and a calculation program.

Some calculators, such as desktop calculators, have the ability to perform specific calculations using specific preset numerical values. Such functions include, for example, a function to calculate consumption tax. When a consumption tax calculation is performed, a preset consumption tax rate is called up and the tax-inclusive price or tax-exclusive price for the input amount is calculated. Calculators that have separate tax-inclusive keys for calculating tax-inclusive prices and tax-exclusive keys for calculating tax-exclusive prices are also known. Furthermore, in recent years, calculators that have tax-inclusive keys and tax-exclusive keys for a number of different tax rates have also become known.

JP 2000-132517 A

When keys for calculating taxes for different tax rates are provided, it is conceivable that while entering data into the calculator, the user may accidentally press a key for a tax rate different from the one originally intended, resulting in a tax calculation different from the one originally intended. In such cases, it is useful to be able to perform the originally intended tax calculation with simple operations.

The present invention aims to provide a calculator and a calculation program that allows the user to easily restore the input state even if a calculation other than the user's original intention is performed.

The calculator of the first aspect of the present invention includes a first calculation unit that performs a first calculation using a first argument on the numeric values when a first instruction input is received after a numeric value is input, a second calculation unit that performs a second calculation using the first argument on the numeric values when a second instruction input is received after a numeric value is input, a first control unit that returns a result of the first calculation to the input state immediately before the first instruction input is received when a second instruction input is received without a numeric value being input after the first calculation is performed, and a second control unit that returns a result of the second calculation to the input state immediately before the second instruction input is received when a first instruction input is received without a numeric value being input after the second calculation is performed.

The calculation program of the second aspect of the present invention causes a processor to execute the following: if a first instruction input is received after a numerical input is received, a first calculation is performed using a first argument on the numerical values; if a second instruction input is received after a numerical input is received, a second calculation is performed using the first argument on the numerical values; if a second instruction input is received after a numerical input is received, but no numerical values are input, after the first calculation is performed, a calculation result of the first calculation is restored to the input state immediately before the first instruction input is received; and if a first instruction input is received after the second calculation is performed, but no numerical values are input, a calculation result of the second calculation is restored to the input state immediately before the second instruction input is received.

The present invention provides a calculator and a calculation program that allow the user to easily restore the input state even if a calculation other than the user's original intention is performed.

FIG. 1 is a diagram illustrating an example of a configuration of a computer according to an embodiment. FIG. 2 is a front view of the appearance of the computer. FIG. 3A is a flowchart showing a tax calculation process of a computer according to an embodiment. FIG. 3B is a flowchart showing the process of tax calculation by the computer according to the embodiment. FIG. 4A is a diagram showing the transition of the states of the display, the input value storage area, the subtotal 1 storage area, and the subtotal 2 storage area when key input is performed according to the first operation. FIG. 4B is a diagram showing the transition of the states of the display, the input value storage area, the subtotal 1 storage area, and the subtotal 2 storage area when key input is performed in accordance with the second operation. FIG. 5 is a diagram showing a transition of the display on the display in the first operation.

FIG. 1 is a diagram showing an example of the configuration of a calculator 1 according to an embodiment. Calculator 1 has a processor 11, a memory 12, an input device 13, a display 14, and a power supply module 15. Calculator 1 may be a desk calculator, a so-called pocket calculator. Calculator 1 may also be various electronic devices that have a function of calculating numerical values other than a pocket calculator. Calculator 1 may also have a configuration other than that shown in FIG. 1.

The processor 11 is a processor that controls various operations of the calculator 1. The processor 11 may be a CPU, an ASIC, an FPGA, or the like. The processor 11 may also be composed of two or more processors. The processor 11 operates as a first calculation unit that performs a tax-inclusive calculation using a first tax rate or a second tax rate. The processor 11 also operates as a second calculation unit that performs a tax-exclusive calculation using a first tax rate or a second tax rate. The processor 11 also operates as a first control unit that returns the calculation result of the first calculation unit to the previous input state. The processor 11 also operates as a second control unit that returns the calculation result of the second calculation unit to the previous input state. The processor 11 also operates as a storage control unit that controls storage in the memory 12. The processor 11 also operates as a display control unit that controls the display of the display 14. Here, the first tax rate is, for example, 10%. The second tax rate is, for example, 8%. The first tax rate and the second tax rate may be changed by the user.

The memory 12 includes a RAM and a ROM. The RAM is a volatile memory and can operate as a storage unit. The RAM is used as a working memory for temporarily storing various data in the processor 11. In the embodiment, the RAM has an input value storage area for storing numerical values input via the numeric keys. The RAM also has a subtotal 1 storage area for storing the result of the tax calculation using the first tax rate. The subtotal 1 storage area has a first total price including tax storage area for storing the total price including tax to which the first tax rate is applied, a first total price excluding tax storage area for storing the total price excluding tax to which the first tax rate is applied, and a first total tax amount storage area for storing the total tax amount to which the first tax rate is applied. The RAM also has a subtotal 2 storage area for storing the result of the tax calculation using the second tax rate. The subtotal 2 memory area has a second total price including tax memory area for storing the total price including tax to which the second tax rate is applied, a second total price excluding tax memory area for storing the total price excluding tax to which the second tax rate is applied, and a second total tax amount memory area for storing the total tax amount to which the second tax rate is applied. The ROM is a non-volatile memory. The ROM stores various programs such as calculation programs for executing various calculation functions. The ROM also stores various specific numerical values used in numerical calculations and the like as arguments. These specific numerical values include, for example, the value of the tax rate used in tax calculation.

The input device 13 is a variety of operation interfaces that allow the user to operate the calculator 1. When an operation using the input device 13 is accepted, an input signal corresponding to that operation is transmitted to the processor 11.

The display 14 is a display unit such as a liquid crystal display. The display 14 displays various information related to the calculator function.

The power supply module 15 supplies power to each circuit of the calculator 1. The power supply module 15 is, for example, a solar cell module. The solar cell module generates power from light irradiated through the light receiving window.

Figure 2 is a front view of the appearance of the calculator 1. As shown in Figure 2, an input device 13 and a display 14 are provided on the front of the housing of the calculator 1.

The input device 13 has numeric keys, arithmetic keys, and function keys. The numeric keys are keys for inputting numeric values, and include, for example, keys corresponding to the numeric values from 0 to 9. The arithmetic keys are keys for performing the four arithmetic operations, and include, for example, keys corresponding to the operators + (addition), - (subtraction), x (multiplication), and ÷ (division), and an = (perform operation) key. The function keys are keys for performing various functions of the calculator 1, and include, for example, an all clear key (AC key), a clear key (C key), and memory keys (MRC key, M+ key, M- key).

Furthermore, in the embodiment, the input device 13 has various tax calculation keys. The tax calculation keys include a tax-inclusive 1 key 131, a tax-exclusive 1 key 132, a tax-inclusive 2 key 133, a tax-exclusive 2 key 134, and a tax calculation total key 135.

The tax-inclusive 1 key 131 is a tax calculation key for performing tax-inclusive calculation using a first tax rate preset as an argument for an inputted numerical value. The tax-exclusive 1 key 132 is a tax calculation key for performing tax-exclusive calculation using a first tax rate for an inputted numerical value. The calculation result calculated by pressing the tax-inclusive 1 key 131 or the tax-exclusive 1 key 132 is stored in the subtotal 1 storage area of the RAM of the memory 12.

The tax-inclusive 2 key 133 is a tax calculation key for performing tax-inclusive calculation using a second tax rate preset as an argument for an inputted numerical value. The tax-exclusive 2 key 134 is a tax calculation key for performing tax-exclusive calculation using a second tax rate for an inputted numerical value. The calculation result calculated by pressing the tax-inclusive 2 key 133 or the tax-exclusive 2 key 134 is stored in the subtotal 2 storage area of the RAM of the memory 12. In this way, in the embodiment, the tax calculation using the first tax rate and the tax calculation using the second tax rate are performed separately.

The tax calculation total key 135 is a key for displaying the total amount of the tax calculation results using the first tax rate, the total amount of the tax calculation results using the second tax rate, and the total amount of the tax calculation results using the first tax rate and the tax calculation results using the second tax rate.

The input device 13 may have a fraction selector 136 and a decimal point selector 137. The fraction selector 136 is a selector for specifying the processing to be performed when a fraction occurs in the tax calculation result. For example, the fraction selector 136 can select the processing to be performed as the fraction processing from among processing such as rounding down and rounding off. The decimal point selector 137 is a selector for specifying how many decimal places to use in the calculation when a decimal number occurs in the tax calculation.

Figures 3A and 3B are flowcharts showing the tax calculation process of the calculator 1 according to the embodiment. The process of Figures 3A and 3B is performed by the processor 11 executing a calculation program stored in the ROM of the memory 12. The normal operation of the calculator 1 other than the tax calculation process is not particularly limited. For example, the processor 11 displays the calculation result on the display 14 according to the user's key input, and performs various functions such as a memory function.

In step S1, the processor 11 determines whether or not a numeric value has been input. If any numeric key is pressed, it is determined that a numeric value has been input. If it is determined in step S1 that a numeric value has been input, the process proceeds to step S2. If it is determined in step S1 that a numeric value has not been input, the process of Figures 3A and 3B ends. In this case, the operation of the calculator 1 proceeds to normal operation.

In step S2, the processor 11 updates the contents of the input value storage area of the RAM in the memory 12 with the numerical input value.

In step S3, the processor 11 displays the entered numerical value on the display 14.

In step S4, the processor 11 determines whether or not the tax-inclusive 1 key 131 has been pressed. When it is determined in step S4 that the tax-inclusive 1 key 131 has been pressed, the process proceeds to step S5. When it is determined in step S4 that the tax-inclusive 1 key 131 has not been pressed, the process proceeds to step S13.

In step S5, the processor 11 performs a tax-inclusive 1 display process. The tax-inclusive 1 display process is a process for displaying a price including tax using a first tax rate. As the tax-inclusive 1 display process, the processor 11 performs a tax-inclusive calculation using the first tax rate on the input numerical value. The processor 11 then displays the result of the tax-inclusive calculation on the display 14.

In step S6, processor 11 updates the contents of the subtotal 1 storage area of the RAM of memory 12 based on the result of the tax-inclusive calculation using the first tax rate. Specifically, processor 11 adds the result of the tax-inclusive calculation using the first tax rate to the tax-inclusive price stored in the first tax-inclusive price total storage area. Processor 11 also adds the tax-excluded price corresponding to the result of this tax-inclusive calculation, i.e., the most recently entered numerical value, to the tax-excluded price stored in the first tax-excluded price total storage area. Processor 11 also adds the tax amount calculated from the result of this tax-inclusive calculation to the tax amount stored in the first tax total storage area.

In step S7, the processor 11 determines whether or not the tax-inclusive 1 key 131 has been pressed. When it is determined in step S7 that the tax-inclusive 1 key 131 has been pressed, the process proceeds to step S8. When it is determined in step S7 that the tax-inclusive 1 key 131 has not been pressed, the process proceeds to step S9.

In step S8, the processor 11 performs processing to display tax value 1 on the display 14. After the processing to display tax value 1, the processing in Figs. 3A and 3B ends. In this case, the operation of the calculator 1 transitions to normal operation. The processing to display tax value 1 is processing to display the tax amount calculated in step S6. That is, if the tax-inclusive 1 key 131 is pressed in succession after the tax-inclusive calculation using the first tax rate, the display on the display 14 switches from displaying the price including tax to displaying the tax amount.

In step S9, the processor 11 determines whether the tax-excluded 1 key 132 has been pressed. When it is determined in step S9 that the tax-excluded 1 key 132 has been pressed, the process proceeds to step S10. When it is determined in step S9 that the tax-excluded 1 key 132 has not been pressed, the process of Figures 3A and 3B ends. In this case, the operation of the calculator 1 proceeds to normal operation.

In step S10, the processor 11 refers to the contents of the input value memory area and displays the previously input numerical value on the display 14.

In step S11, processor 11 clears the contents of the subtotal 1 storage area in the RAM of memory 12 based on the previously input numerical value. Specifically, processor 11 restores the values stored in the first total price including tax storage area, the first total price excluding tax storage area, and the first total tax amount storage area to the values before the tax-inclusive calculation based on the previously input numerical value. The processing in Figures 3A and 3B then ends. In this case, the operation of calculator 1 transitions to normal operation. That is, if the tax-excluded 1 key 132 is pressed without inputting a numerical value after the tax-inclusive calculation using the first tax rate, the result of the previous tax-inclusive calculation is cleared.

In step S12, the processor 11 determines whether the "1 excluding tax" key 132 has been pressed. When it is determined in step S12 that the "1 excluding tax" key 132 has been pressed, the process proceeds to step S13. When it is determined in step S12 that the "1 excluding tax" key 132 has not been pressed, the process proceeds to step S20.

In step S13, processor 11 performs tax-excluded price 1 display processing. Tax-excluded price 1 display processing is processing for displaying the price excluding tax using a first tax rate. As tax-excluded price 1 display processing, processor 11 performs tax-excluded price calculation using the first tax rate for the inputted numerical value. Processor 11 then displays the result of the tax-excluded price calculation on display 14.

In step S14, processor 11 updates the contents of the subtotal 1 storage area of the RAM of memory 12 based on the result of the tax-excluded calculation using the first tax rate. Specifically, processor 11 adds the result of the tax-excluded calculation using the first tax rate to the tax-excluded price stored in the first tax-excluded total price storage area. Processor 11 also adds the tax-inclusive price corresponding to the result of this tax-excluded calculation, i.e., the most recently input numerical value, to the tax-excluded price stored in the first tax-inclusive total price storage area. Processor 11 also adds the tax amount calculated from the result of this tax-excluded calculation to the tax amount stored in the first tax total amount storage area.

In step S15, the processor 11 determines whether the tax-excluded 1 key 132 has been pressed. If it is determined in step S15 that the tax-excluded 1 key 132 has been pressed, the process proceeds to step S16. If it is determined in step S15 that the tax-excluded 1 key 132 has not been pressed, the process proceeds to step S17.

In step S16, the processor 11 performs a process to display tax value 1 on the display 14. After the process to display tax value 1, the processes in Figs. 3A and 3B end. The process to display tax value 1 is a process for displaying the tax amount calculated in step S14. That is, if the tax-excluded 1 key 131 is pressed continuously after the tax-excluded calculation using the first tax rate, the display on the display 14 switches from displaying the price excluding tax to displaying the tax amount.

In step S17, the processor 11 determines whether or not the tax-inclusive 1 key 131 has been pressed. When it is determined in step S17 that the tax-inclusive 1 key 131 has been pressed, the process proceeds to step S18. When it is determined in step S17 that the tax-inclusive 1 key 131 has not been pressed, the process in Figures 3A and 3B ends. In this case, the operation of the calculator 1 proceeds to normal operation.

In step S18, the processor 11 refers to the contents of the input value memory area and displays the previously input numerical value on the display 14.

In step S19, processor 11 clears the contents of the subtotal 1 storage area in the RAM of memory 12 based on the previously input numerical value. Specifically, processor 11 restores the values stored in the first total price including tax storage area, the first total price excluding tax storage area, and the first total tax amount storage area to the values before the tax-excluding calculation based on the previously input numerical value. The processing of Figures 3A and 3B then ends. In this case, the operation of calculator 1 transitions to normal operation. That is, if tax-inclusive 1 key 131 is pressed without inputting a numerical value after the tax-excluding calculation using the first tax rate, the result of the previous tax-excluding calculation is cleared.

In step S20, the processor 11 determines whether or not the tax-inclusive 2 key 133 has been pressed. When it is determined in step S20 that the tax-inclusive 2 key 133 has been pressed, the process proceeds to step S21. When it is determined in step S20 that the tax-inclusive 2 key 133 has not been pressed, the process proceeds to step S28.

In step S21, the processor 11 performs a tax-inclusive 2 display process. The tax-inclusive 2 display process is a process for displaying a price including tax using a second tax rate. As the tax-inclusive 2 display process, the processor 11 performs a tax-inclusive calculation using the second tax rate on the input numerical value. The processor 11 then displays the result of the tax-inclusive calculation on the display 14.

In step S22, processor 11 updates the contents of the subtotal 2 storage area of the RAM of memory 12 based on the result of the tax-inclusive calculation using the second tax rate. Specifically, processor 11 adds the result of the tax-inclusive calculation using the second tax rate to the tax-inclusive price stored in the second tax-inclusive price storage area. Processor 11 also adds the tax-excluded price corresponding to the result of this tax-inclusive calculation, i.e., the most recently entered numerical value, to the tax-excluded price stored in the second tax-excluded price storage area. Processor 11 also adds the tax amount calculated from the result of this tax-inclusive calculation to the tax amount stored in the second tax total storage area.

In step S23, the processor 11 determines whether or not the tax-inclusive 2 key 133 has been pressed. When it is determined in step S23 that the tax-inclusive 2 key 133 has been pressed, the process proceeds to step S24. When it is determined in step S23 that the tax-inclusive 2 key 133 has not been pressed, the process proceeds to step S25.

In step S24, the processor 11 performs a process to display tax value 2 on the display 14. After the process to display tax value 2, the processes in Figs. 3A and 3B end. In this case, the operation of the calculator 1 transitions to normal operation. The process to display tax value 2 is a process for displaying the tax amount calculated in step S22. That is, if the tax-inclusive 2 key 133 is pressed in succession after the tax-inclusive calculation using the second tax rate, the display on the display 14 switches from displaying the price including tax to displaying the tax amount.

In step S25, the processor 11 determines whether the tax-excluded 2 key 134 has been pressed. When it is determined in step S25 that the tax-excluded 2 key 134 has been pressed, the process proceeds to step S26. When it is determined in step S25 that the tax-excluded 2 key 134 has not been pressed, the process of Figures 3A and 3B ends. In this case, the operation of the calculator 1 proceeds to normal operation.

In step S26, the processor 11 refers to the contents of the input value memory area and displays the previously input numerical value on the display 14.

In step S27, processor 11 clears the contents of the subtotal 2 storage area in the RAM of memory 12 based on the previously input numerical value. Specifically, processor 11 restores the values stored in the second total price including tax storage area, the second total price excluding tax storage area, and the second total tax amount storage area to the values before the tax-inclusive calculation based on the previously input numerical value. The processing in Figures 3A and 3B then ends. In this case, the operation of calculator 1 transitions to normal operation. That is, if tax-excluded 2 key 134 is pressed without inputting a numerical value after the tax-inclusive calculation using the second tax rate, the result of the previous tax-inclusive calculation is cleared.

In step S28, the processor 11 determines whether the tax-excluded 2 key 134 has been pressed. When it is determined in step S28 that the tax-excluded 2 key 134 has been pressed, the process proceeds to step S29. When it is determined in step S28 that the tax-excluded 2 key 134 has not been pressed, the process of Figures 3A and 3B ends. In this case, the operation of the calculator 1 proceeds to normal operation.

In step S29, the tax-excluded price 2 display process is performed. The tax-excluded price 2 display process is a process for displaying the price excluding tax using the second tax rate. As the tax-excluded price 2 display process, the processor 11 performs a tax-excluded price calculation using the second tax rate for the inputted numerical value. The processor 11 then displays the result of the tax-excluded price calculation on the display 14.

In step S30, processor 11 updates the contents of the subtotal 2 storage area of the RAM of memory 12 based on the result of the tax-excluded calculation using the second tax rate. Specifically, processor 11 adds the result of the tax-excluded calculation using the second tax rate to the tax-excluded price stored in the second tax-excluded total price storage area. Processor 11 also adds the tax-inclusive price corresponding to the result of this tax-excluded calculation, i.e., the most recently input numerical value, to the tax-inclusive price stored in the second tax-inclusive total price storage area. Processor 11 also adds the tax amount calculated from the result of this tax-excluded calculation to the tax amount stored in the second tax total amount storage area.

In step S31, the processor 11 determines whether the tax-excluded 2 key 134 has been pressed. When it is determined in step S31 that the tax-excluded 2 key 134 has been pressed, the process proceeds to step S32. When it is determined in step S31 that the tax-excluded 2 key 134 has not been pressed, the process proceeds to step S33.

In step S32, the processor 11 performs a process to display tax value 2 on the display 14. After the process to display tax value 2, the processes in Figs. 3A and 3B end. In this case, the operation of the calculator 1 transitions to normal operation. The process to display tax value 2 is a process for displaying the tax amount calculated in step S30. That is, if the tax-excluded 2 key 134 is pressed in succession after the tax-excluded calculation using the second tax rate, the display on the display 14 switches from displaying the price excluding tax to displaying the tax amount.

In step S33, the processor 11 determines whether or not the tax-inclusive 2 key 133 has been pressed. When it is determined in step S33 that the tax-inclusive 2 key 133 has been pressed, the process proceeds to step S34. When it is determined in step S33 that the tax-inclusive 2 key 133 has not been pressed, the process of Figures 3A and 3B ends. In this case, the operation of the calculator 1 proceeds to normal operation.

In step S34, the processor 11 refers to the contents of the input value memory area and displays the previously input numerical value on the display 14.

In step S35, processor 11 clears the contents of the subtotal 2 storage area of RAM in memory 12 based on the previously input numerical value. Specifically, processor 11 restores the values stored in the second total price including tax storage area, the second total price excluding tax storage area, and the second total tax amount storage area to the values before the tax-excluded calculation based on the previously input numerical value. After that, the processing of Figures 3A and 3B ends. In this case, the operation of calculator 1 transitions to normal operation. In other words, if tax-inclusive 2 key 133 is pressed without inputting a numerical value after the tax-excluded calculation using the second tax rate, the result of the previous tax-excluded calculation is cleared.

Figure 4A shows the transition of the states of the display, input value storage area, subtotal 1 storage area, and subtotal 2 storage area when key input is made according to the first operation. The first operation is the operation of pressing the same tax calculation key repeatedly. Here, "key" indicates the type of operation key pressed. "Icon" indicates the type of icon displayed on the display 14. "Display" indicates the numerical value displayed on the display 14. "Input" indicates the contents stored in the input value storage area. "Subtotal 1" indicates the contents stored in the subtotal 1 storage area. Of "Subtotal 1," "Tax Included 1" indicates the contents stored in the first total price including tax storage area, "Tax Excluded 1" indicates the contents stored in the first total price excluding tax storage area, and "Tax 1" indicates the contents stored in the first total tax amount storage area. Similarly, "Subtotal 2" indicates the contents stored in the subtotal 2 storage area. Of "Subtotal 2," "Tax Included 2" indicates the content stored in the second total price including tax storage area, "Tax Excluded 2" indicates the content stored in the second total price excluding tax storage area, and "Tax 2" indicates the content stored in the second total tax amount storage area. Here, in FIG. 4A, the first tax rate is 10% and the second tax rate is 8%.

In the first example of the first operation, as shown in "key", the AC key is pressed, the number "100" is entered, and then the tax-inclusive 1 key 131 is pressed, and then the tax-inclusive 1 key 131 is pressed without entering a number.

When the AC key is pressed, the state of Calculator 1 is cleared. That is, "Input", "Tax Included 1", "Tax Excluded 1", "Tax 1", "Tax Included 2", "Tax Excluded 2", and "Tax 2" are reset to their initial values of "0". Also, "Icon" is set to blank, meaning that nothing is displayed on the display 14. Also, "Display" is set to "0", meaning that the initial value of "0" is displayed on the display 14.

Next, by pressing the tax-inclusive 1 key 131 after inputting the number "100", tax-inclusive calculation is performed using the first tax rate. Accordingly, the contents of "Input", "Tax-inclusive 1", "Excluding tax 1", and "Tax 1" are updated. "Input" is updated to the input number "100". "Tax-inclusive 1" is updated to "110", which is the result of the tax-inclusive calculation. "Excluding tax 1" is updated to the price excluding tax as a result of the tax-inclusive calculation, that is, the input number "100". "Tax 1" is updated to "10". Meanwhile, the contents of "Tax-inclusive 2", "Excluding tax 2", and "Tax 2" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-inclusive icon", and "Tax 1 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-inclusive calculation, "110", is displayed.

Next, when the tax-inclusive 1 key 131 is pressed, "Icon" changes to a state in which the "Tax GT icon", "Tax icon", and "Tax 1 icon" are displayed. Also, "Display" changes to a state in which "10", the tax amount corresponding to the result of the tax-inclusive calculation, is displayed. Meanwhile, "Input", "Tax inclusive 1", "Tax exclusive 1", "Tax 1", "Tax inclusive 2", "Tax exclusive 2", and "Tax 2" are not updated.

In the second example of the first operation, as shown in "key", the AC key is pressed, the number "100" is entered, and then the tax-inclusive 2 key 133 is pressed, and then the tax-inclusive 2 key 133 is pressed without entering a number.

The state when the AC key is pressed is the same as in the first example. Next, by pressing the tax-inclusive 2 key 133 after inputting the number "100", tax-inclusive calculation is performed using the second tax rate. Accordingly, the contents of "Input", "Tax-inclusive 2", "Excluding tax 2", and "Tax 2" are updated. "Input" is updated to the input number "100". "Tax-inclusive 2" is updated to "108", which is the result of the tax-inclusive calculation. "Excluding tax 2" is updated to the tax-excluded price for the result of the tax-inclusive calculation, that is, the input number "100". "Tax 2" is updated to "8". Meanwhile, the contents of "Tax-inclusive 1", "Excluding tax 1", and "Tax 1" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-inclusive icon", and "Tax 2 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-inclusive calculation, "108", is displayed.

Next, when the tax-inclusive 2 key 133 is pressed, "Icon" changes to a state in which the "Tax GT icon", "Tax icon", and "Tax 2 icon" are displayed. Also, "Display" changes to a state in which "8", which is the tax amount corresponding to the result of the tax-inclusive calculation, is displayed. Meanwhile, "Input", "Tax inclusive 1", "Tax exclusive 1", "Tax 1", "Tax inclusive 2", "Tax exclusive 2", and "Tax 2" are not updated.

In the third example of the first operation, as shown in "key", the AC key is pressed, the number "110" is entered, the "tax-excluded 1" key 132 is pressed, and then the "tax-excluded 2" key 132 is pressed without entering a number.

The state when the AC key is pressed is the same as in the first example. Next, by pressing the tax-excluded 1 key 132 after inputting the number "110", a tax-excluded calculation is performed using the first tax rate. Accordingly, the contents of "Input", "Tax-included 1", "Tax-excluded 1", and "Tax 1" are updated. "Input" is updated to the input number "110". "Tax-excluded 1" is updated to "100", which is the result of the tax-excluded calculation. "Tax-included 1" is updated to the price including tax for the result of the tax-excluded calculation, that is, the input number "110". "Tax 1" is updated to "10". Meanwhile, the contents of "Tax-included 2", "Tax-excluded 2", and "Tax 2" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-excluded icon", and "Tax 1 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-excluded calculation, "100", is displayed.

Next, when the tax-excluded 1 key 132 is pressed, "Icon" changes to a state in which the "Tax GT icon", "Tax icon", and "Tax 1 icon" are displayed. Also, "Display" changes to a state in which "10", which is the tax amount corresponding to the result of the tax-excluded calculation, is displayed. On the other hand, "Input", "Tax included 1", "Tax-excluded 1", "Tax 1", "Tax included 2", "Tax-excluded 2", and "Tax 2" are not updated.

In the fourth example of the first operation, as shown in "key", the AC key is pressed, the number "108" is entered, and then the "tax-excluded 2" key 134 is pressed, and then the "tax-excluded 2" key 134 is pressed without entering a number.

The state when the AC key is pressed is the same as in the first example. Next, by pressing the tax-excluded 2 key 134 after inputting the number "108", a tax-excluded calculation is performed using the second tax rate. Accordingly, the contents of "Input", "Tax-included 2", "Tax-excluded 2", and "Tax 2" are updated. "Input" is updated to the input number "108". "Tax-excluded 2" is updated to "100", which is the result of the tax-excluded calculation. "Tax-included 2" is updated to the price including tax for the result of the tax-excluded calculation, that is, the input number "108". "Tax 2" is updated to "8". Meanwhile, the contents of "Tax-included 1", "Tax-excluded 1", and "Tax 1" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-excluded icon", and "Tax 2 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-excluded calculation, "100", is displayed.

Next, when the tax-excluded 2 key 134 is pressed, "Icon" changes to a state in which the "Tax GT icon", "Tax icon", and "Tax 2 icon" are displayed. Also, "Display" changes to a state in which "8", which is the tax amount corresponding to the result of the tax-excluded calculation, is displayed. Meanwhile, "Input", "Tax included 1", "Tax excluded 1", "Tax 1", "Tax included 2", "Tax excluded 2", and "Tax 2" are not updated.

Figure 4B is a diagram showing the transition of the states of the display, input value storage area, subtotal 1 storage area, and subtotal 2 storage area when key input is made according to the second operation. The second operation is an operation of successively pressing different tax calculation keys for the same tax rate. Here, "key", "Icon", "Display", "Input", "Subtotal 1", "Tax included 1", "Tax excluded 1", "Tax 1", "Subtotal 2", "Tax included 2", "Tax excluded 2", and "Tax 2" are the same as in Figure 4A. Also in Figure 4B, the first tax rate is 10% and the second tax rate is 8%.

In the first example of the second operation, as shown in "key", the AC key is pressed, the number "1000" is entered and then the tax-inclusive 1 key 131 is pressed, the number "100" is entered and then the tax-inclusive 1 key 131 is pressed, and then the tax-exclusive 1 key 132 is pressed without entering a number.

When the AC key is pressed, the state of Calculator 1 is cleared. That is, "Input", "Tax Included 1", "Tax Excluded 1", "Tax 1", "Tax Included 2", "Tax Excluded 2", and "Tax 2" are reset to their initial values of "0". Also, "Icon" is set to blank, meaning that nothing is displayed on the display 14. Also, "Display" is set to "0", meaning that the initial value of "0" is displayed on the display 14.

Next, by pressing the tax-inclusive 1 key 131 after inputting the number "1000", tax-inclusive calculation is performed using the first tax rate. Accordingly, the contents of "Input", "Tax-inclusive 1", "Excluding tax 1", and "Tax 1" are updated. "Input" is updated to the input number "1000". "Tax-inclusive 1" is updated to "1100", which is the result of the tax-inclusive calculation. "Excluding tax 1" is updated to the price excluding tax for the result of the tax-inclusive calculation, that is, the input number "1000". "Tax 1" is updated to "100". Meanwhile, the contents of "Tax-inclusive 2", "Excluding tax 2", and "Tax 2" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-inclusive icon", and "Tax 1 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-inclusive calculation, "1100", is displayed.

Next, by pressing the tax-inclusive 1 key 131 after inputting the number "100", tax-inclusive calculation is performed using the first tax rate. Accordingly, the contents of "Input", "Tax-inclusive 1", "Excluding tax 1", and "Tax 1" are updated. "Input" is updated to the input number "100". "Tax-inclusive 1" is updated to "1210" by adding the result of the tax-inclusive calculation. "Excluding tax 1" is updated to "1100" by adding the price excluding tax to the result of the tax-inclusive calculation, that is, the input number "100". "Tax 1" is updated to "1100". Meanwhile, the contents of "Tax-inclusive 2", "Excluding tax 2", and "Tax 2" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-inclusive icon", and "Tax 1 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-inclusive calculation, "110", is displayed.

Next, when the tax-excluded 1 key 132 is pressed, "tax-excluded 1", "tax-excluded 1", and "tax 1" are updated to the state before the previous tax-included calculation based on the previous input values. That is, "tax-included 1" is updated to "1100". "tax-excluded 1" is updated to "1000". "Tax 1" is updated to "100". Meanwhile, "Input" is not updated. Also, the "Icon" display is erased. Also, "Display" is reverted to a state where the previous input value, "100", is displayed. In this way, the result of the previous tax-included calculation is cleared.

In the second example of the second operation, as shown in "key", the AC key is pressed, the number "1000" is entered and then the tax-inclusive 2 key 133 is pressed, the number "100" is entered and then the tax-inclusive 2 key 133 is pressed, and then the tax-exclusive 2 key 134 is pressed without entering a number.

The state when the AC key is pressed is the same as in the first example. Next, by pressing the tax-inclusive 2 key 133 after inputting the number "1000", tax-inclusive calculation is performed using the second tax rate. Accordingly, the contents of "Input", "Tax-inclusive 2", "Excluding tax 2", and "Tax 2" are updated. "Input" is updated to the input number "1000". "Tax-inclusive 2" is updated to "1080", which is the result of the tax-inclusive calculation. "Excluding tax 2" is updated to the tax-excluded price for the result of the tax-inclusive calculation, that is, the input number "1000". "Tax 2" is updated to "80". Meanwhile, the contents of "Tax-inclusive 1", "Excluding tax 1", and "Tax 1" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-inclusive icon", and "Tax 2 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-inclusive calculation, "1080", is displayed.

Next, by pressing the tax-inclusive 2 key 133 after inputting the number "100", tax-inclusive calculation is performed using the second tax rate. Accordingly, the contents of "Input", "Tax-inclusive 2", "Excluding tax 2", and "Tax 2" are updated. "Input" is updated to the input number "100". "Tax-inclusive 2" is updated to "1188" by adding the result of the tax-inclusive calculation. "Excluding tax 2" is updated to "1100" by adding the price excluding tax to the result of the tax-inclusive calculation, that is, the input number "100". "Tax 2" is updated to "88". Meanwhile, the contents of "Tax-inclusive 1", "Excluding tax 1", and "Tax 1" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-inclusive icon", and "Tax 2 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-inclusive calculation, "108", is displayed.

Next, when the tax-excluded 2 key 134 is pressed, "tax-excluded 2", "tax-excluded 2", and "tax 2" are updated to the state before the previous tax-included calculation based on the previous input values. That is, "tax-included 2" is updated to "1080". "tax-excluded 2" is updated to "1000". "Tax 2" is updated to "80". Meanwhile, "Input" is not updated. Also, the "Icon" display is erased. Also, "Display" is reverted to a state where the previous input value, "100", is displayed. In this way, the result of the previous tax-included calculation is cleared.

In the third example of the second operation, as shown in "key", the AC key is pressed, the number "1100" is entered and then the tax-excluded 1 key 132 is pressed, the number "110" is entered and then the tax-excluded 1 key 132 is pressed, and then the tax-inclusive 1 key 131 is pressed without entering a number.

The state when the AC key is pressed is the same as in the first example. Next, by pressing the tax-excluded 1 key 132 after inputting the number "1100", a tax-excluded calculation is performed using the first tax rate. Accordingly, the contents of "Input", "Tax-included 1", "Tax-excluded 1", and "Tax 1" are updated. "Input" is updated to the input number "1100". "Tax-excluded 1" is updated to "1000", which is the result of the tax-excluded calculation. "Tax-included 1" is updated to the price including tax for the result of the tax-excluded calculation, that is, the input number "1100". "Tax 1" is updated to "100". On the other hand, the contents of "Tax-included 2", "Tax-excluded 2", and "Tax 2" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-excluded icon", and "Tax 1 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-excluded calculation, "1000", is displayed.

Next, by pressing the tax-excluded 1 key 132 after inputting the number "110", a tax-excluded calculation is performed using the first tax rate. Accordingly, the contents of "Input", "Tax-included 1", "Tax-excluded 1", and "Tax 1" are updated. "Input" is updated to the input number "110". "Tax-excluded 1" is updated to "1100" by adding the result of the tax-excluded calculation. "Tax-included 1" is updated to "1210" by adding the price including tax to the result of the tax-excluded calculation, that is, the input number "110". "Tax 1" is updated to "110". Meanwhile, the contents of "Tax-included 2", "Tax-excluded 2", and "Tax 2" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-excluded icon", and "Tax 1 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-excluded calculation, "100", is displayed.

Next, when the tax-inclusive 1 key 131 is pressed, "tax-inclusive 1", "tax-exclusive 1", and "Tax 1" are updated to the state before the most recent tax-exclusive calculation based on the most recent input values. That is, "tax-exclusive 1" is updated to "1000". "tax-inclusive 1" is updated to "1100". "Tax 1" is updated to "100". Meanwhile, "Input" is not updated. Also, the "Icon" display is erased. Also, "Display" is reset to a state where the most recent input value, "110", is displayed. In this way, the result of the most recent tax-exclusive calculation is cleared.

In the fourth example of the second operation, as shown in "key", the AC key is pressed, the number "1080" is entered and then the tax-excluded 2 key 134 is pressed, the number "108" is entered and then the tax-excluded 2 key 134 is pressed, and then the tax-inclusive 2 key 133 is pressed without entering a number.

The state when the AC key is pressed is the same as in the first example. Next, by pressing the tax-excluded 2 key 134 after inputting the number "1080", a tax-excluded calculation is performed using the second tax rate. Accordingly, the contents of "Input", "Tax-included 2", "Tax-excluded 2", and "Tax 2" are updated. "Input" is updated to the input number "1080". "Tax-excluded 2" is updated to "1000", which is the result of the tax-excluded calculation. "Tax-included 2" is updated to the price including tax for the result of the tax-excluded calculation, that is, the input number "1080". "Tax 2" is updated to "80". On the other hand, the contents of "Tax-included 1", "Tax-excluded 1", and "Tax 1" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-excluded icon", and "Tax 2 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-excluded calculation, "1000", is displayed.

Next, by pressing the tax-excluded 2 key 134 after inputting the number "108", a tax-excluded calculation is performed using the second tax rate. Accordingly, the contents of "Input", "Tax-included 2", "Tax-excluded 2", and "Tax 2" are updated. "Input" is updated to the input number "108". "Tax-excluded 2" is updated to "1100" by adding the result of the tax-excluded calculation. "Tax-included 2" is updated to "1188" by adding the price including tax to the result of the tax-excluded calculation, that is, the input number "108". "Tax 2" is updated to "88". Meanwhile, the contents of "Tax-included 1", "Tax-excluded 1", and "Tax 1" are not updated. Also, "Icon" is in a state where the "Tax GT icon", "Tax-excluded icon", and "Tax 2 icon" are displayed. These icons will be explained later. Also, "Display" is in a state where the result of the tax-excluded calculation, "100", is displayed.

Next, when the tax-inclusive 2 key 134 is pressed, "tax-inclusive 2", "tax-exclusive 2", and "Tax 2" are updated to the state before the most recent tax-exclusive calculation based on the most recent input values. That is, "tax-exclusive 2" is updated to "1000". "Tax-inclusive 2" is updated to "1080". "Tax 2" is updated to "80". Meanwhile, "Input" is not updated. Also, the "Icon" display is erased. Also, "Display" is reset to a state where the most recent input value, "108", is displayed. In this way, the result of the most recent tax-exclusive calculation is cleared.

Figure 5 shows the transition of the display on the display 14 during the first operation. Note that, during the second operation, only the previously input numerical value is displayed. Therefore, a description thereof is omitted.

First, the AC key is pressed, clearing the display on the display 14. At this time, the display screen on the display 14 is display screen A. On display screen A, the initial value "0" is displayed. No icons or the like are displayed on display screen A.

When the tax-included key or tax-excluded key is pressed after a numerical value is input on the display screen A, the display screen of the display 14 transitions to the display screen B. On the display screen B, for example, when the tax-included 1 key is pressed together with a numerical value, a numerical value 201 representing the result of the tax calculation is displayed as shown on screens b1, b2, b3, and b4. Furthermore, as icons, the tax GT icon 202, the tax-included icon 203, and the tax 1 icon 204 are displayed. On the display screen B, for example, when the tax-included 2 key is pressed together with a numerical value, a numerical value 201 representing the result of the tax calculation is displayed as shown on screens b5, b6, and b7. Further, as icons, the tax GT icon 202, the tax-included icon 203, and the tax 2 icon 205 are displayed. Here, the tax GT icon 202 is an icon indicating that the calculation of the total price including tax, the total price excluding tax, and the total tax amount using the first tax rate is being performed. As described above, when the tax-included key is pressed after the input of a numerical value, a process is performed to update the contents of the subtotal 1 storage area or the subtotal 2 storage area. Tax-inclusive icon 203 is an icon indicating that the number 201 is a price including tax. Tax 1 icon 204 is an icon indicating that the tax calculation was performed using a first tax rate. Tax 2 icon 205 is an icon indicating that the tax calculation was performed using a second tax rate.

When the tax calculation total key 135 is pressed on display screen B, the display screen of the display 14 transitions to display screen C. On display screen C, as shown in screen c1, a numeric value 201 is first displayed, which indicates the total of the tax-inclusive price calculated at the first tax rate and the tax-inclusive price calculated at the second tax rate, i.e., the total of the tax-inclusive price stored in the first tax-inclusive price total storage area and the tax-inclusive price stored in the second tax-inclusive price total storage area. In addition, a tax GT icon 202, a tax-inclusive icon 203, and a total icon 206 are displayed as icons. The total icon 206 is an icon indicating that the numeric value 201 is the total amount.

When the tax calculation total key 135 is pressed on screen c1, the display screen of the display 14 transitions to screen c2. Screen c2 displays a numerical value 201 that indicates the total of the tax-excluded price calculated at the first tax rate and the tax-excluded price calculated at the second tax rate, i.e., the total of the tax-excluded price stored in the first total tax-excluded price storage area and the tax-excluded price stored in the second total tax-excluded price storage area. In addition, a tax GT icon 202, a tax-excluded icon 207, and a total icon 206 are displayed as icons. The tax-excluded icon 207 is an icon that indicates that the numerical value 201 is the tax-excluded price.

When the tax calculation total key 135 is pressed on screen c1, the display screen of the display 14 transitions to screen c3. Screen c3 displays a numerical value 201 that indicates the total tax amount of the tax amount calculated at the first tax rate and the tax amount calculated at the second tax rate, i.e., the total tax amount stored in the first total tax amount storage area and the second total tax amount storage area. Additionally, a tax GT icon 202, a tax icon 208, and a total icon 206 are displayed as icons. The tax icon 208 is an icon that indicates that the numerical value 201 is the tax amount.

When the tax calculation total key 135 is pressed on screen c3, the display screen of the display 14 returns to screen c1. On the other hand, when the tax-inclusive 1 key 131 is pressed on any of screens c1, c2, and c3, the display screen of the display 14 transitions to display screen D. On display screen D, as shown in screen d1, first, a numeric value 201 is displayed that represents the total tax-inclusive price of the tax-inclusive prices calculated at the first tax rate, i.e., the tax-inclusive price stored in the first total tax-inclusive price storage area. In addition, a tax GT icon 202, a tax-inclusive icon 203, a tax 1 icon 204, and a total icon 206 are displayed as icons.

When the tax-inclusive 1 key 131 is pressed on screen d1, the display screen of the display 14 transitions to screen d2. Screen d2 displays a numeric value 201 that indicates the total price excluding tax of the prices excluding tax calculated at the first tax rate, i.e., the price excluding tax stored in the first total price excluding tax storage area. In addition, a tax GT icon 202, a tax-exclusive icon 207, a tax 1 icon 204, and a total icon 206 are displayed as icons.

When the tax-inclusive 1 key 131 is pressed on screen d2, the display screen of the display 14 transitions to screen d3. Screen d3 displays a numeric value 201 representing the tax amount calculated at the first tax rate, i.e., the tax amount stored in the first total tax amount storage area. In addition, a tax GT icon 202, a tax icon 208, a tax 1 icon 204, and a total icon 206 are displayed as icons.

When the tax calculation total key 135 is pressed on any of screens d1, d2, and d3, the display screen of the display 14 returns to display screen C. On the other hand, when the tax-inclusive 2 key 133 is pressed on any of screens c1, c2, and c3, or when the tax-inclusive 2 key 133 is pressed on any of screens d1, d2, and d3, the display screen of the display 14 transitions to display screen E. On display screen E, first, as shown in screen e1, a numeric value 201 representing the total tax-inclusive price of the tax-inclusive prices calculated at the second tax rate, that is, the tax-inclusive price stored in the second total tax-inclusive price storage area, is displayed. In addition, a tax GT icon 202, a tax-inclusive icon 203, a tax 2 icon 205, and a total icon 206 are displayed as icons.

When the tax-included 2 key 133 is pressed on screen e1, the display screen of the display 14 transitions to screen e2. Screen e2 displays a numeric value 201 indicating the total price excluding tax of the prices excluding tax calculated at the second tax rate, i.e., the price excluding tax stored in the second total price excluding tax storage area. In addition, a tax GT icon 202, a tax-excluded icon 207, a tax 2 icon 205, and a total icon 206 are displayed as icons.

When the tax-inclusive 2 key 133 is pressed on screen e2, the display screen of the display 14 transitions to screen e3. Screen e3 displays a numeric value 201 representing the tax amount calculated at the second tax rate, i.e., the tax amount stored in the second total tax amount storage area. In addition, a tax GT icon 202, a tax icon 208, a tax 2 icon 205, and a total icon 206 are displayed as icons.

When the tax calculation total key 135 is pressed on any of screens e1, e2, and e3, the display screen of the display 14 returns to display screen C. When the tax-inclusive 1 key 131 is pressed on any of screens e1, e2, and e3, the display screen of the display 14 returns to display screen D.

As described above, according to the embodiment, when the same tax calculation key with different tax rates is pressed consecutively without inputting a numerical value, the result of the previous tax calculation is cleared. At this time, the numerical value input immediately before is displayed on the display 14. As a result, even if, for example, the user accidentally presses a tax calculation key other than the one originally intended while inputting data into the calculator and a tax calculation other than the one originally intended is performed, the user can quickly recalculate the tax as intended with a simple operation.

In addition, in conventional calculators, pressing a clear key or the like clears the display on the screen, but does not clear the total amount stored in memory, so if there is an input error, the total amount cannot be calculated correctly. This is not possible in the embodiment, causing inconvenience. In contrast, in the embodiment, as the result of the tax calculation is cleared, the contents of the subtotal 1 storage area or subtotal 2 storage area also return to the state they were in before the tax calculation. Therefore, the total amount can also be calculated correctly.

Here, in the embodiment, if tax calculation keys with different tax rates are pressed consecutively without entering a numerical value, the result of the previous tax calculation is cleared. Therefore, the embodiment can be applied to a calculator with only one tax rate.

In addition, in the embodiment, an example of application to tax calculation is described. In contrast, the technology of the embodiment can be applied to various calculators that perform specific calculations using specific preset values. Such specific calculations include currency conversion calculations. In this case, too, if no numerical value is entered and the conversion rate key is pressed repeatedly, the result of the previous conversion calculation can be cleared. In addition, such specific calculations can include powdered medicine audit calculations.

In the embodiment, processing is performed in response to the operation of physical keys. In recent years, calculation programs have become available that use software keys to perform calculations similar to those performed by a calculator. The embodiment can also be applied to such calculation programs that are operated using software keys.

The processes according to the above-described embodiments can be stored as a program that can be executed by processor 11, which is a computer. Alternatively, they can be stored in a storage medium of an external storage device such as a magnetic disk, optical disk, or semiconductor memory and distributed. Then, processor 11 can execute the above-described processes by reading the program stored in the storage medium of the external storage device and having its operation controlled by the read program.

The present invention is not limited to the above-described embodiments, and can be modified in various ways during implementation without departing from the gist of the invention. The embodiments may be implemented in appropriate combination, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combinations selected from the multiple constituent elements disclosed. For example, if the problem can be solved and an effect can be obtained even if some constituent elements are deleted from all the constituent elements shown in the embodiments, the configuration from which these constituent elements are deleted can be extracted as an invention.

The following will addendum to inventions that can be extracted from the embodiments of the present invention.
[1] a first calculation unit that, when accepting a first instruction input after accepting an input of a numerical value, performs a first calculation on the numerical value using a first argument;
a second calculation unit that, when a second instruction input is received after receiving an input of a numerical value, performs a second calculation on the numerical value using the first argument;
a first control unit that, when the second instruction input is received without inputting a numerical value after the first calculation is performed, returns a result of the first calculation to an input state immediately before the first instruction input is received;
a second control unit that, when the first instruction input is received without inputting a numerical value after the second calculation is performed, returns a result of the second calculation to an input state immediately before the second instruction input is received;
A computer comprising:
[2] The computer according to [1], further comprising a first memory control unit that, when the first calculation is performed, if the first calculation has been performed prior to the currently performed first calculation, causes a sum of a numerical value based on the calculation result of the first calculation performed up to the previous time and a numerical value based on the calculation result when the first calculation is currently performed to be stored in the memory unit as a first sum.
[3] When the first control unit returns the calculation result of the first calculation to an immediately preceding input state, the first storage control unit causes the storage unit to store, as a new first sum, a value obtained by subtracting a numerical value based on a calculation result when the first calculation is currently performed from the stored first sum.
The computer according to [2].
[4] The computer according to any one of [1] to [3], further comprising a second memory control unit configured to, when the second calculation is performed, if the second calculation has been performed prior to the current second calculation, store in the memory unit a sum of a numerical value based on the calculation result of the second calculation performed up to the previous time and a numerical value based on the calculation result when the second calculation is currently performed as a second sum.
[5] When the second control unit returns the calculation result of the second calculation to an immediately preceding input state, the second storage control unit causes the storage unit to store, as a new second sum, a value obtained by subtracting a numerical value based on a calculation result when the second calculation is currently performed from the stored second sum.
The computer according to [4].
[6] A display control unit that displays any one of the input numerical values, the result of the first calculation, and the result of the second calculation on a display unit,
The display control unit is
When a numerical value is input, the input numerical value is displayed on the display unit;
When the first calculation is performed, a result of the first calculation is displayed on the display unit;
When the second calculation is performed, a result of the second calculation is displayed on the display unit;
when the result of the first calculation or the result of the second calculation is cleared, the numerical value input immediately before the first calculation or the second calculation is performed is displayed on the display unit.
The computer according to any one of [1] to [5].
[7] The display control unit is
when the first calculation is performed, displaying a first icon indicating that the first calculation has been performed together with a result of the first calculation;
when the second calculation is performed, displaying a second icon indicating that the second calculation has been performed together with a result of the second calculation;
when the inputted numerical value is to be displayed on the display unit, the display of the first icon or the second icon is erased.
The computer according to [6].
[8] The first instruction input is an input of a tax-inclusive key,
the second instruction input is an input of a "tax-excluded"key;
13. The computer according to claim 12, wherein
[9] The first calculation is a tax-inclusive calculation using a first tax rate as the first argument,
The second calculation is a tax-excluded calculation using the first tax rate.
13. The computer according to claim 12, wherein
[10] The first calculation is a tax-inclusive calculation using a first tax rate as the first argument,
The first total value is a total value of the tax amount calculated from the total value of the numerical value based on the calculation result of the tax-inclusive calculation performed up to the previous time and the numerical value based on the calculation result of the tax-inclusive calculation performed this time, and the total value of the numerical value based on the calculation result of the tax-inclusive calculation performed up to the previous time and the numerical value based on the calculation result of the tax-inclusive calculation performed this time.
The computer according to [2] or [3].
[11] Further comprising a display control unit that switches between displaying the result of the first calculation, the total value of the result of the tax-inclusive calculation, and the total value of the tax amount on a display unit.
The computer according to [10].
[12] The second calculation is a tax-excluded calculation using a first tax rate as the first argument,
The second total value is a total value of the tax amount calculated from the total value of the numerical value based on the calculation result of the tax-excluded calculation performed up to the previous time and the numerical value based on the calculation result of the tax-excluded calculation performed this time, and the total value of the numerical value based on the calculation result of the tax-excluded calculation performed up to the previous time and the numerical value based on the calculation result of the tax-excluded calculation performed this time.
The computer according to [4] or [5].
[13] Further comprising a display control unit that switches between the calculation result of the second calculation, the total value of the calculation result excluding tax, and the total value of the tax amount and displays them on a display unit.
The computer according to [12].
[14] when accepting a first instruction input after accepting an input of a numerical value, performing a first calculation on the numerical value using a first argument;
when a second instruction input is received after the input of a numerical value is received, performing a second calculation on the numerical value using the first argument;
when the second instruction input is received without inputting a numerical value after the first calculation is performed, returning a result of the first calculation to an input state immediately before the first instruction input is received;
when the first instruction input is received without inputting a numerical value after the second calculation is performed, returning a result of the second calculation to an input state immediately before the second instruction input is received;
A calculation program for causing a processor to execute the above.

1 Calculator, 11 Processor, 12 Memory, 13 Input device, 14 Display, 15 Power supply module, 131 Tax incl. 1 key, 132 Tax excl. 1 key, 133 Tax incl. 2 key, 134 Tax excl. 2 key, 135 Tax calculation total key, 136 Fraction selector, 137 Decimal point selector.

Claims (14)

a first calculation unit that, when accepting a first instruction input after accepting an input of a numerical value, performs a first calculation on the numerical value using a first argument;
a second calculation unit that, when a second instruction input is received after receiving an input of a numerical value, performs a second calculation on the numerical value using the first argument;
a first control unit that, when the second instruction input is received without inputting a numerical value after the first calculation is performed, returns a result of the first calculation to an input state immediately before the first instruction input is received;
a second control unit that, when the first instruction input is received without inputting a numerical value after the second calculation is performed, returns a result of the second calculation to an input state immediately before the second instruction input is received;
A computer comprising: The computer according to claim 1, further comprising a first storage control unit that, when the first calculation is performed, if the first calculation has been performed before the first calculation currently performed, stores in the storage unit a first total value that is a sum of a numerical value based on the calculation result of the first calculation performed up to the previous time and a numerical value based on the calculation result when the first calculation is currently performed. When the first control unit returns the calculation result of the first calculation to the immediately preceding input state, the first storage control unit causes the storage unit to store a value obtained by subtracting a numerical value based on the calculation result when the first calculation is currently performed from the stored first total value as a new first total value.
3. The computer of claim 2. The computer according to any one of claims 1 to 3, further comprising a second storage control unit that, when the second calculation is performed, stores in the storage unit a sum of a numerical value based on the calculation result of the second calculation performed up to the previous time and a numerical value based on the calculation result when the second calculation is performed this time as a second sum value if the second calculation has been performed before the second calculation currently performed. When the second control unit returns the calculation result of the second calculation to the immediately preceding input state, the second storage control unit causes the storage unit to store a value obtained by subtracting a numerical value based on the calculation result when the second calculation is currently performed from the stored second total value as a new second total value.
5. The computer according to claim 4. a display control unit that displays on a display unit either an input numerical value, a result of the first calculation, or a result of the second calculation;
The display control unit is
When a numerical value is input, the input numerical value is displayed on the display unit;
When the first calculation is performed, a result of the first calculation is displayed on the display unit;
When the second calculation is performed, a result of the second calculation is displayed on the display unit;
when the result of the first calculation or the result of the second calculation is cleared, the numerical value input immediately before the first calculation or the second calculation is performed is displayed on the display unit.
A computer according to any one of claims 1 to 5. The display control unit is
when the first calculation is performed, displaying a first icon indicating that the first calculation has been performed together with a result of the first calculation;
when the second calculation is performed, displaying a second icon indicating that the second calculation has been performed together with a result of the second calculation;
when the inputted numerical value is to be displayed on the display unit, the display of the first icon or the second icon is erased.
7. The computer of claim 6. the first instruction input is an input of a tax-inclusive key,
the second instruction input is an input of a "tax-excluded"key;
A computer according to any one of claims 1 to 7. The first calculation is a tax-inclusive calculation using a first tax rate as the first argument,
The second calculation is a tax-excluded calculation using the first tax rate.
A computer according to any one of claims 1 to 8. The first calculation is a tax-inclusive calculation using a first tax rate as the first argument,
The first total value is a total value of the tax amount calculated from the total value of the numerical value based on the calculation result of the tax-inclusive calculation performed up to the previous time and the numerical value based on the calculation result of the tax-inclusive calculation performed this time, and the total value of the numerical value based on the calculation result of the tax-inclusive calculation performed up to the previous time and the numerical value based on the calculation result of the tax-inclusive calculation performed this time.
4. A computer according to claim 2 or 3. and a display control unit that switches between the result of the first calculation, the total value of the result of the tax-inclusive calculation, and the total value of the tax amount and displays them on a display unit.
11. The computer of claim 10. The second calculation is a tax-excluded calculation using a first tax rate as the first argument,
The second total value is a total value of the tax amount calculated from the total value of the numerical value based on the calculation result of the tax-excluded calculation performed up to the previous time and the numerical value based on the calculation result of the tax-excluded calculation performed this time, and the total value of the numerical value based on the calculation result of the tax-excluded calculation performed up to the previous time and the numerical value based on the calculation result of the tax-excluded calculation performed this time.
6. A computer according to claim 4 or 5. and a display control unit for switching between the result of the second calculation, the total value of the result of the tax-excluded calculation, and the total value of the tax amount and displaying them on a display unit.
13. The computer of claim 12. when a first instruction input is accepted after an input of a numerical value is accepted, performing a first calculation on the numerical value using a first argument;
when a second instruction input is received after the input of a numerical value is received, performing a second calculation on the numerical value using the first argument;
when the second instruction input is received without inputting a numerical value after the first calculation is performed, returning a result of the first calculation to an input state immediately before the first instruction input is received;
when the first instruction input is received without inputting a numerical value after the second calculation is performed, returning a result of the second calculation to an input state immediately before the second instruction input is received;
A calculation program for causing a processor to execute the above.