JPH0214352A - Electronic calculator with graph display function - Google Patents

Abstract

PURPOSE:To execute the display of discontinuous graph by preventing an interval between two points from being linked when coordinate data (y), which continue in an (x)-axis direction, go out of a display area. CONSTITUTION:At first, a distance (x) from an xmin is set to 0 and the (y) at such a time is operated by an arithmetic part 5. Then, the (x) and (y) are respectively stored in registers 3E and 3F. Next, the (x) is set to +1 and the (y) is found in the same way. Then, they are stored in registers 3G and 3H. The data of these two points are read. When one point, out of the two points at least, is a coordinate in an area which is set to 3I-3L, the graph to connect the two points is written to a graph display buffer 6A. When the both points are coordinates out of the area, the linking of the above mentioned two points is not executed. When the data of the registers 3G and 3H are moved to the 3E and 3F, the (x) is +1, and the (x) is in the set area, the above mentioned graph preparation is repeated.

Description

[Detailed description of the invention] [Technical field of invention J This invention can display functional formulas in graphs. Concerning large computers.

[Prior art] A small electronic calculator that can display any functional formula in a graph has been considered, but when displaying a functional formula in a graph with this calculator, the range of variables Each item is set in advance by manual key operation, and a graph is displayed based on the settings.

[Problems with the prior art] However, the above-mentioned total/H4! ! In this case, lines are not connected to the coordinates beyond the display area defined by the range of the variables x and Y, so the graph around the display area is displayed in pieces, and the complete graph cannot be displayed. It has disappeared, giving it a strange visual feel.

[Objective of the Invention] The present invention aims to provide a small electronic calculator with a graph display function that can connect lines even to coordinate points beyond the display area and display a complete graph. purpose.

[Key Points of the Invention] When displaying a graph of a functional formula, this invention controls whether or not to connect the previous coordinate point and the current coordinate point with a line, depending on the positional relationship between the previous coordinate point and the current coordinate point. The main point is that.

[Embodiment] An embodiment of the present invention will be described below with reference to one drawing.

Fig. 1 is a circuit diagram of a small electronic calculator equipped with a graph display function. In Fig. 1, l is a key manual section, and this key manual section l has a numeric keypad IA provided in a normal calculator.
, Function key IB, Function key Ic for inputting the calculation formula of the function, Gratzgi ID to specify the graph display mode of the function formula, input mode for each range data of independent variable X and dependent variable Y included in the function formula. At least a range key IE for specifying a function and an EXE (execution) key IF for instructing execution of function calculations, etc. are provided, and signals from each key are sent to the control unit 2 and processed.

The control unit 2 consists of a ROM (read only memory) that stores programs that control all operations of this computer, an instruction decoder, etc.;
Various control signals are given to the execution pointer 4, the calculation section 5, and the display buffer section 6.

The memory unit 3 consists of a RAM (random access memory), an address decoder, etc., and includes a pointer register 3A, a cursor pointer 3B, and a workpiece, in which the execution pointer 4 set by the control unit 2 when performing a function calculation is temporarily saved. Register 3C, flag register 3D in which three flags (described later) are set respectively, previous coordinates (χ0, yo) for displaying a graph when executing a function operation
are set respectively in χ0 register 3E, yo register 3F, current coordinates (χ, y) are set in χ register 3G, 3T register 3H1, the minimum value and maximum value of the range data of independent variable χ are set respectively. χmin register 31. χmax register 3J, minimum value of range data of dependent variable y.

Y m i n register 3 in which maximum i1 is set respectively
In the ymax register 3L, the actual value at the coordinates (χ, y) for graph display is written to X m
Each display data is temporarily saved from the graph display buffer 6A and text display 7 buffer 6B, which constitute the display buffer section 6, when performing either text display or graph display, which will be described later. evacuation area A (3
F) and evacuation area B (3Q).

Each data of the function formula inputted from the key input unit 1 is written to each address of the formula buffer 7 indicated by the execution pointer 4, and then read into the calculation ff1s at the time of calculation.

The arithmetic unit 5 calculates the functional formula output from the formula buffer 7 under the control of the control unit 2 using the registers 3A to 3Q of the memory unit 3.

Then, when the calculation unit 5 executes the function calculation, the data for displaying the graph is read out from the memory unit 3 and displayed by the packer unit 6.
In addition, when normal numerical display etc. is performed, the data for that is sent to the text display buffer 6B, and the display data is sent to the display section 8 and displayed as a graph, a value, etc. is displayed.

The display unit 8 consists of a liquid crystal display device, for example, and has 96 pixels in the X direction.
Data is displayed using dots (coordinate points) each having 64 dots in the Y direction.

The flag register 3D is a range flag that is set according to the operation of the range key IE, and a numeric flag that is set to flag 1'' when a number is entered using the numeric keypad IA when the cursor is not at the end of the line. , the cursor is not at the end of the line, and if the cursor is moved after setting the number, it has an update flag that will set 57 lag 1°'.

Next, the operation will be explained with reference to FIGS. 2 to 7. Let us now consider, for example, the case where the first-order functional expression % expression % (1) is calculated.

In this case, the range key IE and the numeric keypad I
A is operated in advance to preset the minimum and maximum values of the range data for the independent variable χ in the χmin register 3 and χmax register 3J, and the ymin register 3
Similarly, the ymax register 3L is also preset with the minimum and maximum range data for the variable ay.

Next, when the above-mentioned function formula (1) is input by operating the graph key ID, function key IC, function key IB, and EXE key IF, addresses 0 to 3 of the formula buffer 7 are filled with data as shown in FIG. , and each data of the function expression (1) is written by being addressed by the execution pointer 4.

Furthermore, data rENDJ of execution pointer r3J is EXE
This is END code data written when operating the key IF.

Then, according to the operations shown in the flowcharts of FIGS. 4 to 6, the functional calculation of equation (1) is performed by the calculation section 5, and a graph of the result is displayed on the display section 8.

That is, in the main flowchart shown in FIG. 4, first, in step M1, the first pointer (address "O") of the execution pointer 4 is transferred and saved to the pointer register 3A, and y.

Data rFFJ (hexadecimal code) is written to register 3F, and χ register 3G is cleared.

Next, in step M2, χmin register 3I, χma
Using the range data preset in the x register 3J and the data in the χ register of Oj, the calculation of the formula shown in the figure is executed, and the actual value of the independent variable X when the χ coordinate is 0 is calculated. Data indicating a numerical value (currently data preset in the χmin register 3I) is obtained and set in the χm e m o register 3M. That is, the numerical value at the coordinate (χ=0) of the first display dot in the X-coordinate direction is determined.

Next, in step M3, the address "0" saved in the pointer register 3A is returned to the execution pointer 4, and in the next step M4, this address "0" is changed to "3".
The functional operation of the (+) expression in the formula buffer 7 up to 0 is executed, and the first answer is set in the ymemo register 3N.Next, in step M5, it is determined whether or not the answer is an operation error. If YES, the process proceeds to step M6, where hexadecimal code rFFJ indicating error data is written in the y register 3H, and then the process proceeds to step M9.

On the other hand, if the answer is No in step M5, step M7. M8 is executed, and the Y coordinate calculation (in this case, calculation to obtain the coordinates of the first display dot in the Y coordinate direction) and its (x
, y) is sent to the graph display buffer 76A, and a process of lighting the display dot on the display section 8 is executed. The process then proceeds to step M9.

In step M9, χ0 register 3 is transferred from χ register 3G.
The current calculation result data is transferred and saved to E as the previous calculation result data, and similarly, the current calculation data is transferred and saved from the y register 3H to the yO register 3F as the previous calculation data.

Next, in step MIO, the data in χ register 3G is +1
Then, in step Mll, it is determined whether the resulting data has become "96" or more, which is larger than the maximum displayed to/to r9sJ in the X direction.

In this case, of course, the answer is No and the process returns to step M2, and each coordinate of (x, y) from the 2nd # onward is set to step M2.
〜Mll, and then step M
When the result is YES in 11, the calculation ends, and as a result, the graph shown in FIG. 3 is displayed on the display unit 8.

Next, referring to FIG. 5, the Y coordinate calculation in step M7 will be explained in detail. First, in step Yl, the illustrated Y
The calculation of the formula to obtain the coordinate value is stored in the y me m o register 3N, ymin register 3, and ymax register 3L.
is executed according to the data set respectively in
The resulting data is set in the y register 3H as y coordinate data.

Next, in step Y2, the set data is converted into a qi number by rounding, and then in step Y3, it is determined whether the converted data is smaller than the minimum position coordinate rQJ in the Y coordinate direction. . If YES, overrange data is sent to the y register 3H (step Y5), and the process ends. That is, it is determined that the coordinate point obtained this time has gone outside the display area, and the process explained in FIG.
Then, it is determined whether the data converted into an integer is greater than or equal to r64, which is greater than the maximum coordinate "63" in the Y coordinate direction. If YES, the process proceeds to step Y6, where underrange data is set in the y register 3H, and the coordinate point found this time is set outside the display area. Therefore, similar to step Y5 above, the corresponding display process is performed in the flowchart of FIG. 6 below.

On the other hand, if the answer in step Y4 is NO, the current flow ends, and the process proceeds to the flowchart of FIG. 6, where a line is connected to the previous coordinate point and a graph is displayed.

Next: According to Figure 56, the rDra shown in step M8 above is
The operation of "w process" will be specifically explained. First, step D
In I, the data in yo register 3F is error data rF
It is determined whether it is FJ or not, and if the answer is YES, this flow ends and no display operation is performed for this coordinate.

On the other hand, if NO, proceed to step D2 and y.

It is determined whether the data in the register 3F is "over range" or not. If NO, the process further advances to step D3 and it is determined whether the data in the y register 3H is "over range" or not. If YES, the case is as shown in FIG. 7(A), in which the current coordinate point is outside the display area, and the previous coordinate point is within the display area. In such a case, the process further advances to step D4 to display a line connecting both coordinate points, that is, in FIG.
The dot indicated by klJ is lit up, although it was not lit up in the past, so the graph is drawn all the way to the boundary line of the display area, making it very easy to see.

On the other hand, if the result in step D3 is No, the range is not over range either last time or this time, so the process goes to step D5 and the two coordinate points are connected and displayed normally.

Furthermore, if YES is determined in step D2, the process proceeds to step D6, where it is determined whether the data in the y register 3H is "over range" or not. If NO, this means that the previous coordinate point is outside the display area and the current coordinate point is outside the display area. Since the coordinate points are within the display area, which is the opposite of FIG. 7(A), the process advances to step D7 to draw a graph up to the boundary line of the display area.

On the other hand, if YES in step D6, this means that both the previous time and this time are outside the display area, as shown in Figure 7 (B), and in this case, the two coordinate points are not connected and the graph is not displayed. .

In the above embodiment, the coordinates of the variable ay were determined based on the range data of the variable χ, but of course this relationship may be reversed.

[Effects of the Invention] As explained above, the present invention provides a method for automatically creating graph display data using @ calculation from each range data of variables in a function and their relational expressions. Depending on the order relationship with the coordinate points of , connect two points nn if both coordinate points are in the display area, and connect two points nn if one coordinate is outside the display area.

1 in the direction from the coordinate point inside the display area to the coordinate point outside the display area
Since this is a small electronic calculator equipped with a graph display function that controls the graph to extend to the boundary of the display area, the graph is always displayed up to the boundary of the display area, and has the advantage of being able to display graphs that are very easy to read.

[Brief explanation of the drawing]

Fig. 1 is a circuit configuration diagram of an embodiment of the present invention, Fig. 2 is a diagram showing the relationship between an example of an input function formula and the execution pointer 4, and Fig. 3 is a graph showing the calculation and display of the above function formula. 4 to 6 are flowcharts for explaining the operation, and FIG. 7 is a diagram showing cases in which the coordinate points are displayed and cases in which they are not displayed depending on the corresponding positional relationship between the current and previous coordinate points. IA: Numeric keypad, IB: old function key, C: function key, 10: graph key, IE: range key, IF: group EX
E (Execution) Key 2...Control section, 3A...
・Pointer register. 3B...Cursor pointer, 3C...
Work register, 3D... Range flag, 3E
......χ0 register, 3F...yo
Register, 3G...χ register, 3H...
・・y register, 3■・・・・χmin register, 3J°°・・・・χmax register, 3K・・ymin register, 3L・・・・・・ymax
Renstar 3 M--°-°-X m e m O register, 3 N-...-y m e mO register, 3
F, 3Q... Save area, 4... Execution pointer, 5... Arithmetic unit, 6A... Graph display buffer, 7...... Formula buffer, 8.
・・・・・・Display section Figure ζV Figure Figure i-;

Claims (1)

[Claims] Matrix display means, input means for inputting a functional formula, storage means for storing the functional formula, range data input means for inputting range data indicating the range of a variable, and the range data a range data storage means for storing, a calculation means for sequentially calculating coordinate data constituting a graph of the functional formula from the range data of the variable and the functional formula; and a calculation means for storing the coordinate data calculated by the calculation means. a second coordinate storage means for storing the previous coordinate data calculated by the calculation means; and coordinate data stored in the first coordinate storage means and the second coordinate storage means. is within the display area of the matrix type display means; and when the judgment means determines that both coordinate data are within the display area, a and a graph creation means for displaying a graph connecting the coordinate data, and when the judgment means determines that only one of the coordinate data is within the display area, a graph is displayed that connects the A small electronic type having a graph display function, characterized in that it is equipped with graph correction means for extending the graph to the display area boundary of the matrix type display means in the direction of the coordinate point indicated by the coordinate data that is determined not to be present. calculator.