JPH11161803A - Graph display device, its method and recording medium recording display program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display a graph expressing inputted data without previously specifying the sort of a regression graph. SOLUTION: When numeral data for plotting a graph are inputted by the operation of various keys in a key input part 12, a CPU 11 discriminates the number of inputted numerical data, calculates a functional expression of a degree corresponding to the number of numerical data and displays a graph on a display part 16 based on the calculated functional expression. Since the functional expression corresponding to the inputted data can be calculated without previously inputting specification for the degree of the functional expression, a graph suitably approximating plural inputted numerical data can easily be displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graph display device for drawing a graph according to input data, a graph display method, and a recording medium storing a graph display program.

[0002]

2. Description of the Related Art Conventionally, in an electronic computer having a function calculating function, when a type of regression graph that can be displayed (the degree of a functional equation) and a plurality of numerical data are input to draw a graph, the input is performed. Expressed by a function expression of the given order,
A graph approximating a plurality of numerical data can be displayed.

For example, when a plurality of numerical data are input to a computer, a predetermined X, Y coordinate range is set.
A plurality of input numerical data are plotted, and a graph corresponding to the plotted plural numerical data is displayed on the XY coordinate system on the display screen according to the type of regression graph (N-order regression) instructed by the user. Is drawn.

[0004]

As described above, in the conventional graph display device, a plurality of numerical data can be approximated by inputting a type of regression graph (order of a function formula) and a plurality of numerical data which can be displayed. You could display a graph. However, if it is not clear what kind of functional formula should be applied to multiple numerical data to create a graph, specifying an incorrect function formula order will display a graph that does not approximate multiple numerical data. I will. In this case, even if a graph is displayed, it is not possible to easily grasp what type of graph (functional expression) the plurality of input data is represented by.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and does not require the type of regression graph to be specified in advance.
It is an object of the present invention to provide a graph display device, a graph display method, and a recording medium that stores a graph display program, which can display a graph representing input data.

[0006]

According to the present invention, there is provided a data input means for inputting data for drawing a graph, a data number determining means for determining the number of data input by the data input means, A function formula calculating means for calculating a function equation of an order corresponding to the number of data determined by the determining means in accordance with the data input by the data input means; and a function formula calculated by the function formula calculating means. And a graph display means for displaying a graph.

In other words, when displaying a graph corresponding to the input data, the type of the graph (the order of the functional expression) is determined according to the number of input data. Need not be input, and since a function expression corresponding to the input data is calculated, a graph that appropriately approximates the plurality of input numerical data is displayed.

Each time data is input by the data input means, a graph is displayed based on a function equation of an order corresponding to the number of data determined by the data number determining means. Thus, every time data is input, a graph corresponding to the data input up to that time is displayed, so that the graph is deformed.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an electronic circuit of the graph display device according to the embodiment of the present invention. The present graph display device is configured by a computer that reads programs recorded on various recording media, and whose operation is controlled by the read programs.

As shown in FIG. 1, a graph display device according to this embodiment includes a CPU 11, a key input unit 12, a ROM,
13, a RAM 14, a display drive circuit 15, a display unit 16, a position detection circuit 17, a tablet 18, and a recording medium reading unit 20.

The CPU 11 controls the entire apparatus, and is stored in advance in the ROM 13 in response to a key operation signal from the key input unit 12 or a position detection signal detected by the position detection circuit 17. The system program is started, a graph display process is executed according to the system program, and operation control according to various operation modes is performed. The CPU 11 is connected to a RAM 14 in addition to the key input unit 12 and the ROM 13, and is connected to a display unit 16 via a display drive circuit 15.
The tablet 18 is connected via the position detection circuit 17. Further, a recording medium reading unit 20 is connected to the CPU 11.

Note that the CPU 11 is not limited to the program stored in the ROM 13, and may read the program recorded in the recording medium 21 by the recording medium reading unit 20 and store the program in the RAM 14 for execution.

The key input unit 12 is for inputting instructions and data for defining the operation of the graph display device, and includes numerical keys,
Data input keys 12 including character keys, symbol keys, etc.
a, a data key 1 for displaying a data input screen for inputting data (numerical data) for graph display
2b ("data"), a graph key 12c for instructing the start of drawing a graph corresponding to the input data
(“Graph”), a move key 12d (“Move”) for instructing the start of processing for moving the displayed graph in the display screen, and displaying the displayed graph in accordance with input data in the display screen. A transformation key 12e (“deformation”) for transforming, and a decision key 1 for instructing the completion of the transformation of the displayed graph and the decision of various processes.
2f ("confirm"), and cursor keys 12g for various selections and designations are provided. Although not shown, it is assumed that various keys are provided in addition to the function keys for executing various functions.

The ROM 13 stores in advance, in addition to a system program for controlling the entire operation of the graph display device, control processing programs and the like corresponding to various operation modes. RA
M14 stores various data handled in the graph display device, and includes a display register 14a, a designated expression register 14b, an expression register 14c, and a data register 14.
d, graph drawing register 14e, graph flag 14
f, coordinate storage register A14g, coordinate storage register B1
4h and the like are provided.

Display data to be displayed on the display section 16 is developed and stored as bitmap data in the display register 14a. The designated formula register 14b indicates a functional formula to be displayed on a graph selected from a plurality of functional formulas (N-order regression functions (N = 1, 2, 3,...)) By operating the key input unit 12. The data is entered.

The equation register 14c stores data such as a function equation (regression function) obtained in accordance with data input by operating the key input section 12. The data register 14d stores data input for displaying a graph, and stores numerical data based on an X coordinate value and a Y coordinate value.

The graph drawing register 14e is a work area used for drawing (developing) a graph according to the formula data stored in the formula register 14c. The on-graph flag 14f is a flag F indicating that a point (designated point) on the graph as a reference for movement is in a designated state when executing a process of moving the displayed graph on the display screen. is there.

In the coordinate storage register A14g, the coordinates of a point before the start of movement specified as a movement reference when the process of moving the displayed graph on the display screen is stored.

In the coordinate storage register B14h, the coordinates of a point after the start of movement designated as a reference for movement when the process of moving the displayed graph on the display screen is stored.

The display drive circuit 15 is controlled by the CPU 11 based on various data stored in the RAM 14 to
The display section 16 drives and controls the display of graphs, function expressions, and the like.

The display section 16 is composed of, for example, a liquid crystal display capable of color display, and performs various displays under the control of the display drive circuit 15. The position detection circuit 17 detects the coordinates corresponding to the display screen based on the voltage signal generated by the tablet 18 and outputs the coordinates as the coordinate data.
Notify U11.

The tablet 18 is provided on the display screen of the display unit 16, generates a voltage signal corresponding to the position touched by the pen 19, and outputs the voltage signal to the position detection circuit 17.

The recording medium reading section 20 writes / reads a program or data on / from the recording medium 21. As the recording medium 21, for example, various media such as a floppy disk, a hard disk, a CD-ROM, and a DVD can be used.

Next, the operation of the graph display device having the above-described configuration will be described. 2 to 4 are flowcharts showing the graph display processing by the graph display device.

First, it is assumed that the system power of the graph display device is turned on, and the graph display mode is selected by operating a mode key (not shown). The graph display device according to the present embodiment is provided with a regression graph mode for displaying a regression graph (a graph based on a regression function) in the graph display mode.

When the regression graph mode is selected, the CPU
11 starts a control processing program corresponding to the regression graph mode from various control processing programs stored in the ROM 13 and displays an initial screen corresponding to the mode on the display unit 16 by controlling the display drive circuit 15. Let it.

Here, the data key 12 of the key input unit 12
When b is pressed (step A1) and execution of graph data input is instructed, the CPU 11 displays a data input screen for displaying a regression graph.

FIG. 5 shows an example of a data input screen when the data key 12b is pressed, and an example of a data input operation procedure (the order of keys operated in the key input unit 12). The data input screen is provided with a field for inputting an X coordinate value and a Y coordinate value indicating a coordinate point in the XY coordinate system.

After the data key 12b of the key input section 12 is pressed and a data input screen is displayed, when the numeric key in the data input key 12a is pressed, the CPU 11
Inputs numerical data corresponding to the pressed numerical key, temporarily stores the numerical data in the data register 14d of the RAM 14, and displays the numerical value at the current cursor position on the display screen (step A2). Here, it is assumed that at least two or more numerical data are input.

As shown in FIG. 5B, an X coordinate value and a Y coordinate value of a plurality of coordinate points are input by an operation in which a numerical key and a cursor key 12g are combined. FIG.
(B) shows an example of a state where three coordinate points have been input.

In this way, a plurality of input coordinate points can be displayed in a graph without specifying a regression function of a graph to be displayed, or selected from a plurality of regression functions prepared in advance. A graph can be displayed according to the regression function.

When a regression function is selected in advance, display of a regression graph menu for selecting a regression graph is instructed. The regression graph menu includes the types of regression functions (regression graphs) that can be displayed (primary, secondary,
, Quaternary,...) (X, x ² , x ³ , x ⁴ ,
...) are provided. Each item corresponds to a plurality of function keys (not shown) provided in the key input unit 12, and is selected by pressing the function key.

When the function formula is selected, the CPU 11 stores it in the designation formula register 14b of the RAM 14. The regression graph menu may not be displayed when a display instruction is issued, but may be automatically displayed at a timing when a selectable situation is reached. Instead of using the function keys, a regression graph menu may be displayed in the lower area of the display screen for displaying graphs, and an instruction may be given by operating the tablet 18 using the pen 19.

Here, when the graph key 12c is depressed and the execution of the graph display is instructed (step A3), the CP
U11 determines whether or not a function expression for graph display has been selected in advance from the regression graph menu with reference to the designation expression register 14b of the RAM 14 (step A4).

When the function formula is selected, the CPU 11
Calculates a functional expression based on the numerical data stored in the data register 14d in the selected regression. CPU11
Is the formula data of the formula calculated according to the selected regression,
The data is stored in the formula register 14c of the RAM 14, and based on the formula data, a graph to be displayed is created in the graph drawing register 14e and displayed on the display unit 16 (step A6).

When performing a graph display based on the input numerical data, the CPU 11
The maximum value and the minimum value of the input numerical data stored in d are detected, and a range for drawing a graph is set based on the detected maximum value and minimum value. That is, on the graph display screen of the display unit 16, X is set so that a graph corresponding to the input numerical data can be displayed in an appropriate range.
The display position and the change interval (pitch) of the maximum value and the minimum value of each of the coordinate axis and the Y coordinate axis are set. The CPU 11
After setting as described above, a graph is displayed.

On the other hand, when no function formula is selected, C
The PU 11 detects the number of input numerical data (coordinate data) with reference to the data register 14d (Step A5).

If the number of input data is two (step A7), the CPU 11 calculates a first-order function formula based on the two numerical data stored in the data register 14d (step A7). A8). Similarly,
If the number of input data is three, a quadratic function is calculated (steps A7 and A9), and if the number of data is four, a cubic function is calculated (step A7). ,
A10) If the number of data is 5, a fourth-order function formula is calculated (steps A7 and A11).

The CPU 11 converts the equation data of the calculated equation into
The data is stored in the expression register 14c of the RAM 14, and a graph is created and displayed on the display unit 16 (step A12). Further, the CPU 11 displays a function formula calculated in accordance with the number of input numerical data at a predetermined position on a graph display screen.

For example, in the example shown in FIG. 5B, a quadratic function formula is calculated because three coordinate data are input. Therefore, after inputting the numerical data, the graph key 12
When the execution of the graph display is instructed by c, FIG.
As shown in (c), a graph by a quadratic function is displayed, and a function formula “Y1 = x ² −3x + 2” is displayed.

As described above, even if the type (function formula) of the regression graph to be displayed is not specified, a function formula of an order corresponding to the number of input numerical data is automatically calculated and the graph is displayed. It is possible to display a graph based on a function expression of an appropriate order even if it is not clear what kind of function expression should be applied to multiple numerical data to create a graph. it can. Therefore, the number of operations until the graph is displayed is reduced, and it is possible to easily understand what graph (functional expression) the plurality of input data is represented by.

Next, the processing (movement, deformation) for the graph displayed as described above will be described. First,
The processing of moving the graph will be described with reference to the flowchart shown in FIG.

When the move key 12d of the key input section 12 is pressed (step A15 in FIG. 3) and execution of graph movement is instructed, the CPU 11 shifts to a graph movement mode. In the graph movement mode, the graph displayed on the display unit 16 can be moved according to an operation by the pen 19.

In the graph movement mode, the tablet 1
The position detection circuit 1 is operated by operating the pen 19 on the position detection circuit 8.
When notified that the pen has been turned on (a state in which the pen tip of the pen 19 is in contact with the coordinate detection surface of the tablet 18) from step 7 (step A16), the CPU 11 determines whether the graph is currently being displayed. Determine.

When a graph is being displayed, the CPU 1
1 detects the coordinates of the position where the pen is turned on (step A18). Further, the CPU 11 calculates an integer coordinate closest to the detected coordinate in the graph display coordinate system (step A19). The CPU 11 displays the designated point (designated point) based on the calculated coordinates, and also displays the designated coordinate value in the graph display coordinate system (step A20). When the designated point is on the displayed graph, the designated point is a reference point when executing a process of moving the graph on the display screen.

The CPU 11 refers to the flag 14f (flag F) on the graph in the RAM 14 to determine whether the flag F is "1", that is, whether the specified point has already been specified on the graph. Determine (Step A2)
1).

If the flag F is "0", the CP
U11 determines whether the designated point designated by the pen 19 is on the graph using the equation data stored in the equation register 14c corresponding to the currently displayed graph (step A22).

When it is determined that the designated point is not on the graph, the CPU 11 continues to input a position instruction with the pen 19 as it is. For example, by moving the pen 19 on the tablet 18 so that the locus intersects the line of the graph with respect to the displayed graph, the step A is performed.
At 22, it is determined that the input coordinates are on the graph, and a designated point serving as a reference for moving the graph is set on the graph.

When the coordinates on the graph are designated by the pen 19 (step A22), the CPU 11 causes the RA to indicate that the designated point has been set on the graph.
The flag 14f (flag F) on the graph of M14 is set to “1”, and the coordinates of the designated point before the graph is moved are set to R.
The data is stored in the coordinate storage register A14g of the AM 14 (step A24).

The CPU 11 continues to input a position instruction by the pen 19 until the pen 19 is turned off (pen A is away from the coordinate detection surface of the tablet 18) (step A27). Step A1
8, A19, A20).

When the flag 14f (flag F) on the graph is "1" (step A21), the CP
U11 moves the position of the designated point on the graph designated by the pen 19 and displays the graph at the destination by, for example, a virtual line (step A25). Further, the CPU 11 stores the coordinates of the moved designated point in the coordinate storage register B14h (step A26).

When the position indicated by the pen 19 is moved to an arbitrary position and the pen is turned off (step A27),
The CPU 11 moves the coordinate point of the designated point before the movement of the graph stored in the coordinate storage register A14g to the coordinate point of the designated point designated as the destination of the graph stored in the coordinate storage register B14h. A graph is created (step A29).

Further, the CPU 11 calculates the function of the graph after the movement based on the amount of change between the coordinate point of the specified point before the movement of the graph and the coordinate point of the specified point after the movement, and the expression data stored in the expression register 14c. An equation is calculated (step A30).

The CPU 11 causes the display unit 16 to display the graph created in step A29 and the function formula calculated in step A30 (step A3).
1). This completes the movement of the graph.
U11 sets the flag 14f (flag F) on the graph to "0".
And the coordinate storage register A14g is cleared (step A32).

FIG. 6 shows a specific example of graph movement in the graph movement mode. This specific example is shown in FIG.
As shown in (a), the case where the move key 12d is pressed while a plurality of graphs are displayed and an instruction to shift to the graph move mode is given is shown.

In the graph movement mode, as shown in FIG. 6B, when a coordinate point is specified on the graph, the graph to be moved is specified, and the specified point as the reference of the graph movement is changed. Set above.

When the pen 19 is moved in a state where the designated point is set, as shown in FIG. 6C, the target graph follows the movement of the pen tip position of the pen 19. To be moved.

When the pen tip of the pen 19 is moved to an arbitrary position and the pen is turned off, a graph is displayed at the destination as shown in FIG. 6D, and a function expression representing the graph at the destination is displayed. Is displayed.

The displayed graph can be arbitrarily moved on the graph display screen by a simple operation. Therefore, as shown in FIG. 6E, when there are a plurality of numerical data, a graph display in which the coordinates of each numerical data are plotted is used to show what kind of graph these numerical data are represented. You can also move the graph on the screen and check the fit.

When the graph is moved, the operation of moving the graph is explicitly instructed to the graph display device by operating the move key 12d, but when the graph is displayed, the movement is instructed. Pen 1 without doing
The displayed graph may be moved by the operation of the tablet 9 by the user 9.

In this case, when the coordinate data is input by operating the pen 19 while the graph is being displayed, it is determined that the execution of the movement of the graph is instructed, and the designation on the graph is performed based on the input coordinate data. The points are obtained, and the operation described above is performed.

Next, the processing for transforming the graph will be described with reference to the flowchart shown in FIG. When the deformation key 12e of the key input unit 12 is pressed (step A14 in FIG. 3) and execution of graph deformation is instructed, the CPU 1
1 shifts to the graph deformation mode. In the graph deformation mode, the graph displayed on the display unit 16 can be deformed according to the input numerical data.

In the graph deformation mode in the present embodiment, a first graph for creating a graph in accordance with newly input numerical data regardless of numerical data input to display the currently displayed graph. It is assumed that there is a method and a second method of creating a graph in accordance with newly input or deleted numerical data, including numerical data input so far. Here, the first method will be described as an example.

When execution of the graph transformation mode is instructed,
The CPU 11 determines whether a graph is currently being displayed (step A33). If the graph is being displayed, the CPU 11 allows the user to select a graph to be transformed from the displayed graphs (step A34). Note that any method may be used to select a specific graph from a plurality of graphs. If only one graph is displayed, the graph is unconditionally set as an object to be transformed.

Here, when a numerical key in the data input keys 12a is pressed and numerical data for displaying a graph is input (step A35), the CPU 11 inputs numerical data corresponding to the pressed numerical key. And temporarily stores it in the data register 14d of the RAM 14 (step A
36).

The CPU 11 detects the number of input numerical data (coordinate data) with reference to the data register 14d (step A37). If the number of input data is one, a graph cannot be created, and the process returns to step A35 to wait for input of the next numerical data.

Similarly, when numerical data is input and the number of data becomes two, the CPU 11
A first-order function formula is calculated based on the two numerical data stored in d (step A39).

The CPU 11 converts the formula data of the calculated formula into
The data is stored in the expression register 14c of the RAM 14, and a graph is created and displayed on the display unit 16 (step A43). Here, when the confirmation key 12f is pressed to instruct the confirmation of the graph deformation (step A44), C
The PU 11 displays the function formula calculated in accordance with the input number of numerical data at a predetermined position on the graph display screen (step A45).

On the other hand, when the determination of the graph deformation is not instructed and the numerical data is successively input, the CPU 11 similarly calculates the functional expression based on the number of the input numerical data, And is displayed on the display unit 16. That is, when the number of input data becomes three, a quadratic function formula is calculated (step A3).
8, A40), when the number of data becomes four, a cubic function formula is calculated (steps A38, A41), and when the number of data becomes five, a quaternary function formula is calculated. (Steps A38 and A42), and the corresponding graphs are displayed (step A43).

Accordingly, by inputting an arbitrary number of numerical data and instructing the user to confirm the deformation by the enter key 12f, a graph based on the newly input numerical data is substituted for the previously displayed graph. Can be displayed. At the same time, a function expression corresponding to the graph after the deformation can be displayed.

FIG. 7 shows a specific example of graph deformation in the graph deformation mode. In this specific example, FIG.
(A), the modified key 12e in a state where one graph (graph is expressed by a function formula y = x ²⁾ is displayed is pressed, it indicates if the transition to the graph deformation mode is instructed ing.

In the graph deformation mode, as shown in FIG. 7B, two new numerical data (coordinate points (0,-
When (2) (1, 5)) is input, a graph based on the newly input numerical data is displayed instead of the graph display shown in FIG. Here, since two pieces of numerical data are in a state of being input, a graph represented by a linear function expression is displayed.

Subsequently, one numerical data (coordinate point (2,
When 2)) is input, three numerical data including the additionally input numerical data are in a state of being input, so that as shown in FIG. Is transformed into a graph.

Further, one point of numerical data (coordinate point (−1,
When 1)) is input, four numerical data are in the input state, so that the data is transformed into a graph represented by a cubic function expression as shown in FIG. When data (coordinate points (5, 113) are input, five numerical data are in an input state, so that the graph is transformed into a graph represented by a quartic function expression.

Here, when the enter key 12f is depressed to instruct the finalization of the graph deformation, a function expression representing the currently displayed graph is displayed together with the graph as shown in FIG. 7 (e). You.

In the above description, only the case of inputting numerical data is described. However, the numerical data previously input may be arbitrarily deleted. In this case, it is assumed that, in accordance with the deletion of the numerical data, a function formula of an order corresponding to the number of remaining numerical data is calculated based on the remaining numerical data, and a graph is displayed.

In this way, by making it possible to arbitrarily add or delete numerical data, a graph can be created by trial and error, and a desired graph can be easily created.

In the first method in the above-described graph deformation mode, the graph is displayed based on the newly input numerical data regardless of the previously displayed graph. By using the method, a graph can be created in accordance with newly input or deleted numerical data, including the numerical data of the currently displayed graph.

For example, if one point of numerical data (coordinate points) is input while the graph shown in FIG. 7A is displayed, the previously displayed graph is represented by a quadratic function. Since three numerical data have already been input, a cubic function formula is calculated according to the four numerical data, and a graph is displayed.

Also in the case of the second method, a graph can be created by trial and error in the same manner as in the first method, by allowing arbitrary deletion including the numerical data already input. be able to.

As described above, the graph can be modified by arbitrarily adding and deleting numerical data in the graph modification mode even with the graph already created.

[0082]

As described above, according to the graph display device of the present invention, the data input means for inputting data for drawing a graph and the data number for discriminating the number of data input by the data input means are provided. Determining means for calculating a function formula of an order corresponding to the number of data determined by the data number determining means in accordance with the data input by the data input means; and calculating the function formula by the function formula calculating means. Since a graph display means for displaying a graph based on a function expression is provided, when displaying a graph according to the input data, the type of the graph (the degree of the function expression) depends on the number of input data. Since it is determined, there is no need to input the specification of the order of the function expression in advance,
Further, since a function formula according to the input data is calculated, it is possible to display a graph that appropriately approximates the plurality of input numerical data.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an electronic circuit of a graph display device according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a graph display process performed by the graph display device according to the embodiment.

FIG. 3 is a flowchart for explaining a process of moving a graph.

FIG. 4 is a flowchart for explaining a graph deformation process;

FIG. 5 is a diagram showing a specific example of a graph display process.

FIG. 6 is a diagram showing a specific example of graph movement in the graph movement mode.

FIG. 7 is a diagram showing a specific example of graph deformation in a graph deformation mode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... CPU 12 ... Key input part 13 ... ROM 14 ... RAM 15 ... Display drive circuit 16 ... Display part 17 ... Position detection circuit 18 ... Tablet 19 ... Pen 20 ... Recording medium reading part 21 ... Recording medium

Claims (4)

[Claims] 1. A data input means for inputting data for drawing a graph, a data number determining means for determining the number of data input by the data input means, and a data number determined by the data number determining means Function calculating means for calculating a function formula of an order according to the data input by the data input means, and graph displaying means for displaying a graph based on the function formula calculated by the function formula calculating means. And a graph display device. 2. A graph is displayed each time data is input by said data input means, based on a function formula of an order corresponding to the number of data determined by said data number determination means. 2. The graph display device according to 1. 3. A step of inputting data for drawing a graph, a step of determining the number of input data, and a function formula having an order corresponding to the determined number of data is added to the input data. And displaying the graph based on the calculated function formula. 4. A computer comprising: data input means for inputting data for drawing a graph; data number determining means for determining the number of data input by the data input means; A function formula calculating means for calculating a function formula of an order corresponding to the number of data according to the data input by the data input means; and displaying a graph based on the function formula calculated by the function formula calculating means. A recording medium on which a graph display program for functioning as a graph display means is recorded.