JPS626255B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides a method for reading a sequential file in which keyed records are recorded, in which a range of keys is specified and records having keys belonging to the specified key range can be read from the sequential file at high speed. This relates to the method of reading organization files. The finite element method is used for structural analysis, fluid analysis, electromagnetic analysis, etc. FIG. 1 is for explaining the case where the amount of deformation of a plate is determined by the finite element method. In Fig. 1, 1 to 24 are node numbers,
Or it shows the number of the finite element. When the rigidity matrix of the plate is 〓, the load vector is 〓, and the amount of deformation of each part is 〓, the formula 〓・〓=〓 holds true. The purpose of structural analysis is to know the amount of deformation when force is applied. When determining the amount of deformation of each part using the finite element method, first, the stiffness and load are calculated for each element based on the material and nodal coordinate values for the finite element. In this calculation, the formula 〓i・〓=〓i is used. Next, add the stiffness and load of each finite element for each node to assemble the entire equation. In this calculation,

[Formula] The following formula is used. FIG. 2 shows a sequential file. When performing structural analysis using a finite element method using a digital computer, a large number of records (for example, tens to tens of thousands) corresponding to each finite element are recorded in the sequential file. In each record, four node numbers are written as keys, and a stiffness matrix is written as data. Since it is impossible to store all of the data recorded in the sequential file in the main memory, the data is divided into a plurality of blocks and the stiffness matrix data is read in blocks. In this method of dividing into blocks, as shown in Figure 3, a set of records having node numbers 1 to 4 as a key is defined as block 1, and a set of records having node numbers 5 to 8 as a key is defined as block 1. Let the set be block 2, and let the set of records having any one of node numbers 9 to 12 as a key be block 3. The following is as shown in FIG. In the conventional technology, when reading block 1 from a sequential file, the sequential file is read from beginning to end to extract block 1, and when reading each of blocks 2 to 6, the same process is performed. I'm going. Therefore, when attempting to read blocks 1 to 6 from a sequential file as shown in FIG. 2 using the conventional method, the number of records read is 15×6=90, which significantly increases the time required for reading. SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks, and to provide a sequential file reading method that allows records having keys belonging to a specified key range to be read from a sequential file at high speed. It is said that Therefore, the sequential file reading method of the present invention is a sequential file reading method in which a plurality of blocks consisting of a group of records having keys in a specified range are read from a sequential file having keyed records. 1 to nth entry field, and i-th (i=1, 2, ......, n)
The entry field has a specified range setter in which the key range of block i is entered, and the first to nth entry fields, and the i-th (i = 1, 2, ......, n) entry field contains the block i. a record position register device in which a first record position and a last record position of i are recorded;
means for continuing the sequential file from beginning to end while referring to the contents of the specified range setter and recording the first record position and last record position of each block in the record position register device; The present invention is characterized by comprising means for reading blocks from a file while referring to recorded information recorded in the record position register device. Hereinafter, the present invention will be explained with reference to the drawings. FIG. 4 explains one embodiment of the present invention. In FIG. 4, 31 is a record position counter, 32 is a specified range counter, 33 is a record position register device, 34 is a search determiner, 35 is a record position setter, 36 is a specified range setter, 3
7 is a reader, 38 is a controller, and 39 is a sequential file for input. The system of FIG. 4 will be explained with reference to FIG. The record position counter 31 holds the current record of the input file 39. The record position register device 33 has a first entry field to a sixth entry field, and the first record position number and the last record position number of block i are written in the i-th entry field. Specified range counter 32
indicates the number of blocks to be read. The search determiner 4 includes a record position counter 31 and a record position register device 3.
3 and notifies the processing device of the start and end of reading, and when the end of reading is detected, the contents of the counter 32 are incremented by 1, and the input file is input to the first record position of the next block. 39 is requested from the controller 38. The designated range setter 36 has first to sixth entry fields, and the i-th entry field is filled with the node number of block i. For example, the specified range setting device 36
Node numbers 1, 2, 3, and 4 are entered in the first entry field. The record position setting device 35 compares the key number sent from the reader 37 with the contents of the specified range, and if there is a match, writes the current record number in the corresponding entry field of the record position register device 33. do. The first record number written in the entry field of the record position register device 33 is written in the left field and right field of the entry field, and the second and subsequent record numbers are overwritten in the right field. The record reading operation is performed as follows. First, the node numbers of blocks 1 to 6 are entered in the designated range setter 36. Next, records 1 to 15 are read, data is written to the record position register device 33, and block 1 is read. As a result, the first record position number and the last record position number for each of blocks 1 to 6 are written to the record position register device 33. From now on, the record position register 33 is referred to when reading blocks 2 to 6. will be held. According to the embodiment shown in FIG. 4, reading of blocks 1 to 6 as shown in FIG. 3 can be performed in 15+6+6+6+6+3=42 (times). FIG. 5 shows a second embodiment of the invention. In FIG. 5, 40 is an input file, 41
is the output file, 42 is the work file, 43 and 4
4 is a record position register device, 45 and 46 are reading control sections, and 47 is a block assembly section. The second embodiment is suitable when there are a large number of blocks, and it divides the large number of blocks into a plurality of groups, first selects one group, and then selects blocks from the selected group. It is a choice. The record position register device 43 records the first record position and the last record position of the group, and the record position register device 44 records the first record position and the last record position of the block. First of all,
Records are read from the input file 40, and all records within the range specified by the record position register device 43 are stored in the work file 42. Next, records are read from the work file 42, each block is assembled based on the contents of the record position register device 44, and the assembled blocks are stored in the output file 41. As is clear from the above description, according to the present invention, blocks having keys in a specified range can be read from a sequential file at high speed.

[Brief explanation of the drawing]

Figure 1 is a diagram explaining the case where the amount of deformation of a plate is determined by the finite element method, Figure 2 is a diagram explaining a sequential file, and Figure 3 is a diagram showing blocks, node numbers held as keys by records to which blocks belong, and blocks. FIG. 4 is a block diagram of one embodiment of the present invention, and FIG. 5 is a block diagram of a second embodiment of the present invention. 31...Record position counter, 32...Specified range counter, 33...Record position register device, 34...Search determiner, 35...Record position setter, 36...Specified range setter, 37...
Reader, 38...controller, 39...sequential file, 40...input file, 41...output file, 42...work file, 43 and 44...record position register device, 45 and 46...reading Control section, 47...Block assembly section.

Claims (1)

[Claims] 1 A reading method for a sequential file in which multiple blocks consisting of a group of records with keys in a specified range are read from a sequential file having keyed records, which has the first to nth entry fields and the i(i =
1, 2, . …
..., n) The record position register device in which the first record position and last record position of block i are recorded in the entry field, and the sequential organization file from the beginning while referring to the contents of the specified range setter. means for reading to the end and recording the first record position and last record position of each block in the record position register device; and means for reading the block from the sequential file by recording the recorded information recorded in the record position register device. A sequential file reading method characterized by having a means for reading while referring to the file.