JPH0524544B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides an electronic graph capable of scrolling and displaying the remaining portion of the graph that cannot be completely displayed on the screen along the locus of the graph. It relates to electronic devices such as display devices or scientific calculators with graph display functions.

<Prior art> Conventionally proposed scientific calculators with a graph display function use virtual screens (buffers) for each of the top, bottom, left and right screens in order to display the remaining portion of the graph that cannot be completely displayed on the display screen. The remaining portions of the graphs on the virtual screen are displayed on the display screen by operating the cursor keys.

<Problems to be Solved by the Invention> However, in the above-mentioned scientific calculator with a graph display function, the remaining part of the graph can only be displayed for one screen in the vertical and horizontal directions, so the entire graph cannot be displayed. The problem is that it cannot be displayed. Further, in order to solve this problem, a method of preparing a large number of virtual screens (buffers) can be considered, but this method has the drawback of requiring a large capacity memory and increasing costs.

Therefore, an object of the present invention is to calculate the remaining part of the graph that cannot be completely displayed on the display screen by calculation, and sequentially scroll the remaining part of the graph according to the calculation result along the trajectory. An object of the present invention is to provide an electronic device that can display the entire graph on a display screen without providing a separate memory.

<Means for solving the problem> A trace instruction key, a means for sequentially calculating the remaining portion of the graph that cannot be completely displayed on the screen in response to the operation of the trace instruction key, and a method using the calculation means. Comparing means for comparing sequentially obtained results and display screen coordinates; and scrolling means for determining a scrolling direction based on the output of the comparing means and sequentially displaying the remaining portions of the graph on the screen. It is characterized by being prepared.

<Function> In the present invention, when the trace instruction key is operated, the remaining portion of the graph that cannot be completely displayed on the screen is sequentially calculated by the calculating means, and the sequentially calculated calculations are performed by the scrolling means. Based on the results, the remaining portions of the graph are sequentially scrolled and displayed along the trajectory. Therefore, the entire graph can be displayed without providing many virtual screens (buffers).

<Example> FIG. 1 is a plan view of a scientific calculator with a graph display function according to the present invention. In the figure, 1 is the scientific calculator body provided on the left side of a flexible cover 2 that can be folded in two from the center, and 3 is the cover 2.
It is a key input device installed on the right side of the
This key input device is electrically connected to the main body 1 of the scientific calculator, and allows key input to the main body in the same way as the key input device on the main body side.

5 constitutes a display device, and in particular 6 indicates a graph display section which is composed of a 96 x 32 dot LCD (liquid crystal panel) and is capable of displaying 16 digits x 4 rows of characters and graphs; A status display section is shown for displaying a graphic symbol or the like related to a specific key when a specific key is operated to notify that the operating key is in a specific state. 8 is a mode changeover switch, which can be changed by sliding the
COMP mode (mainly a mode for performing various calculations), STAT mode (a mode related to statistics),
It is configured so that it can be switched to AER- and AER-mode (algebraic expression storage mode), respectively.
A label 9 indicates the type of graph to be displayed on the graph display section 6.

SOLVE is a root-finding key for finding the intersection (root-finding) of multiple graphs displayed on the screen, GRAPH is a graphic command key that is operated before entering the formula for the graph to be displayed.
This command is executed by operating the execution key (DRAW key).

AUTO is the autograph command key to automatically set the Y-axis direction range of the graph related to the input formula and graph it. DRAW is the graph display execution key. PLOT is the command to display coordinates (points) on the graph screen. key, LINE is a command key that connects two points on the graphics screen with a straight line, ZOOM is an execution key to enlarge or reduce the displayed contents of the graphics screen at a constant magnification, G.CL is a key that clears all the graphics screen except the coordinate axes. It is.

Figure 2 shows the block configuration, and to explain a little based on this figure, 3 and 4 are key input devices;
5 is a display device composed of a graph display section 6 and a status display section 7, and 8 is a mode changeover switch. Also, 10 is a ROM that stores various programs.
(read-only memory), 11 is a CPU (central processing unit) that controls various calculations and other blocks based on the program in ROM 10, 12 is a
This RAM (read/write memory) has a capacity of 8K bytes, and is a general-purpose RAM in which a variable memory group 13, an array memory group 14, the actual contents of the array, a key input buffer, etc. are provided.

Note that the array memory group 14 does not store actual numerical values, but stores a pointer to an address in the general-purpose RAM 15 and the size of the array.

Further, the key input devices 3 and 4 are provided with a total of 90 key switches, and by operating these keys, power can be turned on and off, calculation formulas can be input, and various commands can be executed. Each key is operated in combination with other keys, the content displayed on the status display section 7, and the setting position of the mode switch.
Reference numeral 16, each having 1 to 5 cutouts, is a communication interface circuit.

FIG. 3 is a main processing flowchart of the scientific calculator according to the present invention, and the operation will be explained based on this diagram. A brief explanation of the terms used in the flowcharts from FIG. 3 onwards is as follows.

(1) Xsft, Ysft...Number of scroll dots in the graph display section 6 (2) XPdot, YPdot...XY coordinates of the dot on the graph that is currently blinking (3) XRdot, YRdot...XY coordinates of the XPdot, YPdot on the screen (4) Xmax (min), Ymax (min)...Display range on screen (5) Xdot, Ydot...Xmax (min), Ymax (min)
The size of X and Y per dot on the screen is determined by
The trace function mode is activated when a graph such as f(x) is displayed or when a key is operated (S1). In the trace function mode, the trace starting point (dot) of the graph is determined by processing according to the flowchart shown in FIG. 4, and is displayed blinking as shown in FIGS. 5A to 5C. In addition,
When a key is pressed, the cursor blinks at the right edge of the screen as much as possible. By the way, Figure 5A is an example of the display by the process of step n3, where XPdot=Xmax, YPdot=f
In the process (Xmax), the dot to be blinked is at the far right end of the screen, its X coordinate is Xmax, and its Y coordinate is f(Xmax). Also, Figure 5B shows the steps.
This is an example of the display resulting from the process of step n6, and FIG. 5C is an example of the display resulting from the process of step n5. FIG. 6 shows the specific processing contents of step n4 in FIG.

When the trace start point is displayed blinking as described above, the key or key press is detected in steps S2 to S5 in Figure 3, and which key was pressed is set in the work area. Later (S3, S5), proceed to step S7. In addition,,
If no key has been pressed, the process proceeds to step S6, where it is checked whether the clear key or any other graph function key has been pressed, and if it has been pressed, the process is terminated.

The specific processing contents of step S7 are as shown in FIG. To explain this processing flow, first make initial settings (P1), then set the X and Y coordinates of the dot on the graph that should blink.
Find XPdot and YPdot. And step P3,
Check if there is scrolling in the Y direction using P5,
If scrolling is necessary, step P4, P6
Find the number of dots to scroll with. Similarly,
After examining scrolling in the X direction in steps P7, P8, and P9, it is determined in step P10 whether scrolling is necessary or not. If scrolling is necessary, proceed to step P11 and perform Xsft, Ysft.
After scrolling by (dot) in the XY direction, proceed to step P12. On the other hand, if there is no need to scroll, the process immediately advances from step P10 to step P12. Then, in step P12, the scrolled graph is displayed on the graph display section 6, and in step P13, the next dot on the graph to be blinked is displayed.
Find XPdot, YPdot and make them blink.

In this way, or by operating the key (trace instruction key), the remaining portion of the graph that cannot be displayed on the screen is calculated one after another by the calculation means, and based on the successively calculated results, The remaining portions of the graph can be sequentially scrolled and displayed along the locus, and the trace start point of the graph can be displayed blinking.

<Effects of the Invention> As described in detail above, according to the present invention, the parts of the graph that cannot be completely displayed on the screen are sequentially calculated, and the results sequentially obtained by the calculation means are compared with the display screen coordinates, The configuration for determining the scrolling direction allows the user to always capture the graph on the screen by specifying scrolling, no matter what direction the graph extends.
Further, the entire graph can be displayed without providing any virtual screen (buffer), and costs can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a plan view of a scientific calculator with a graph display function according to the present invention, Fig. 2 is a block configuration diagram of the same, and Fig. 3 is a plan view of a functional calculator with a graph display function according to the present invention.
4, 6, and 7 are process flowcharts, and FIGS. 5A, 5B, and 5C are diagrams showing trace starting points. 1 is the main body, 2 is the cover, 6 is the graph display section, 1
1 is CPU, 12 is RAM.

Claims (1)

[Scope of Claims] 1. In an electronic device capable of calculating an input calculation formula and creating and displaying a graph based on the calculation result, a trace instruction key is provided, and in response to the operation of the trace instruction key, a graph is displayed on the screen. means for sequentially calculating the remaining portion of the graph that could not be displayed; a comparing means for comparing the results sequentially obtained by the calculating means with display screen coordinates; determining a scrolling direction based on the output of the comparing means; An electronic device comprising scrolling means for sequentially displaying the remaining portions of the graph on the screen.