JPH04436Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a small electronic calculator equipped with a graph display function that graphs and displays a functional formula with simple key operations.

[Prior art and its problems] Conventionally, in small electronic calculators such as personal computers and pocket computers,
Create a program such as BASIC, display a graph by inputting data such as function formulas and numerical values, and display a blinking point (hereinafter referred to as a "pointer") on the display line. Something that shows the coordinates of a pointer is being considered.

When displaying coordinate data of a pointer on the screen in a small electronic calculator such as a personal computer or a pocket computer, the coordinate data is displayed regardless of the range of the displayed coordinates or the display accuracy of the display device. Numerical values were always displayed with a certain number of digits, for example up to 8 decimal places.

However, in cases where the coordinate data of the pointer on the screen is displayed, as mentioned above, the coordinate data is displayed as a numerical value with a certain number of digits, so the display accuracy of the displayed pointer may be affected. It is not possible to know the number of effective digits or the accuracy of displayed dots.

[Purpose of the invention] This invention was made in view of the above-mentioned circumstances, and was designed to provide a graph display function that can also display the coordinate data of the pointer in accordance with the display precision of one dot. The purpose is to provide a small electronic calculator with the following features.

[Summary of the invention] This invention calculates the display accuracy of one dot on the display section from the range data and the number of display dots, and displays the coordinate data of the pointer according to the calculation result.

[Embodiment of the invention] An embodiment of the invention will be described below with reference to the drawings. Figure 1 shows the circuit configuration.
is the key input section. This key input section 11 includes
Numeric keypad 11a for inputting numerical data, function key 11b for specifying calculation details, function key 11c, and graph key 11 for displaying graphs.
d. Trace key 11e for displaying the pointer traced on the display line;
←→Y" key 11f, left movement key to specify leftward movement of the pointer during tracing ("" in the figure)
) 11g, and a right movement key (represented as "" in the figure) 11h, which also specifies movement to the right.
are provided, and when these keys are operated, the key operation data is sent to the control unit 12. Control part 1
Reference numeral 2 controls the circuit according to key operation data from the key input unit 11, and includes a graph display buffer 13 that stores graph display data and a text display buffer 14 that stores text display data such as range data. , a pointer control unit 15 that controls the position of the display pointer, and an execution pointer 16 that specifies the address of a formula buffer (described later).
Control data is sent to the memory unit 17 composed of RAM and the like. This memory section 17
contains a graph register 17 for storing function formulas.
a, an X register 17b that stores X coordinate data of the display pointer on the graph display; a Y register 17c that also stores Y coordinate data; an AX register 17d that stores effective numerical data on the graph display for the X coordinate of the display pointer; Also stores effective numerical data on the graph display for the Y coordinate.
AY register 17e, x register 17f that stores the number of display dots in the X coordinate direction, y register 17g that stores the number of display dots in the Y coordinate direction, xmin register 17h that stores the display range, xmax register 17i, ymin register 17j, ymax A register 17k, an xmemo register 17 for storing calculated X coordinate data of the display pointer, and an ymemo register 17m for storing Y coordinate data are provided.
8 and data input/output. This calculation section 18
In addition to the memory section 17, the pointer control section 1
5. Inputs and outputs data to and from the formula buffer 19, which stores the function formula inputted from the key input unit 11, whose address is designated by the data from the execution pointer 16, and displays graphs and pointers and their coordinate data. It performs the calculation operation of
The calculation result data is sent to the graph display buffer 13 and text display buffer 14.
In addition to control commands from the control unit 12, control commands are also input to the graph display buffer 13 and text display buffer 14 from the pointer control unit 15, and data to be stored by these controls is input to the display unit 20. Output to. This display section 20 is
For example, 201 dots vertically x horizontally using a liquid crystal display element.
It is composed of a dot matrix of 201 dots, and when only graph data is input from the graph display buffer 13, the graph is displayed in full screen. When data is being input, a graph and pointer are displayed in the upper row, and coordinate data is displayed in the lower row.

Next, the operation of the above embodiment will be explained. Second
Figure a shows the graph display state of the display section 20, and it is assumed that the display section 20 is displaying a graph corresponding to the mathematical formula y= ^X2 . At this point, the above formula y=x ² is stored in the formula buffer 19 and the graph formula register 17a of the memory section 17, respectively. Furthermore, x of the memory section 17
The register 17f and y register 17g store the number of display dots "201" in the X and Y coordinate directions, respectively, and the xmin register 17h, xmax register 17i, ymin register 17j and ymax register 17k store the X and Y coordinates. Data "-1", "1", "-1", and "1" indicating the display range of are stored, respectively.

Here, when the pointer on the graph is moved using the left movement key 11g or right movement key 11h of the key input section 11, the coordinate data of the pointer is displayed on the lower part of the display section 20, as shown in FIG. processing is performed. That is, in the figure, first, as shown in step S01, the coordinate data of the pointer displayed on the graph is calculated. For example, if the pointer is displayed at the position indicated by point B on the display unit 20, the X coordinate data of this pointer is "0.09".
After being stored in xmemo register 17,
It is sent to the calculation section 18. In the calculation unit 18, this
Substitute the coordinate data into the formula data "y=x ² " read from the formula buffer 19, perform calculations, and use the calculation result "0.0081" as the Y coordinate data.
Store and set in ymemo register 17m.

When the calculation of the coordinate data is completed in this way, the process proceeds to step S02, where the X coordinate data of the xmemo register 17 set in step S01,
The Y coordinate data of the ymemo register 17m are each indexed, and the X register 17b and Y register 17 are
Set input to c. In this case, the data "0.09" stored in the xmemo register 17 is converted into an index and input into the X register 17b as "9×10 ^-2 ", and the data "0.0081" stored in the ymemo register 17m is converted into an index. The result becomes "8.1×10 ^-3 " and is input to the Y register 17c.

Next, as shown in step S03, the display precision for one dot in the X and Y coordinates is calculated and input to the AX register 17d and AY register 17e. The display accuracy for one dot of the X coordinate is the value stored in the xmax register 17i and xmin.
The difference from the value stored in the register 17h, that is, X
This is obtained by dividing the coordinate range data by the number of display dots in the X coordinate direction stored in the x register 17f minus 1. In this case, the data stored in the xmax register 17i is "1", and the data stored in the xmin register 17h is "-".
1”, the data stored in the x register 17f is “201”
Therefore, the calculation is (1-(-1))/(20-1), and the solution "0.01" is input and set in the AX register 17d as the display accuracy for one dot of the X coordinate. Similarly, the display accuracy for one dot in the Y coordinate is determined by the difference between the value stored in the ymax register 17k and the value stored in the ymin register 17j,
In other words, the range data of the Y coordinate is stored in the y register 1.
1 from the number of displayed dots in the Y coordinate direction stored in 7g
In this case, the data stored in the ymax register 17k is "1", the data stored in the ymin register 17j is "-1", and the data stored in the y register 17g is "201".
Therefore, the calculation is (1-(-1))/(201-1), and the solution "0.01" is input and set in the AY register 17e as the display accuracy for one dot of the Y coordinate.

Thereafter, in step S04, the display precision data for one dot of the X and Y coordinates input and set in the AX register 17d and AY register 17e in step S03 are respectively indexed and newly added to the AX register 17d and AY register. 1
7e. In this case, AX register 17
The values of d and AY register 17e are both "0.01"
Therefore, "1.0×10 ² " is newly set in both registers 17d and 17e.

Next, proceeding to step S05, the X register 1
7b, the exponent parts of the exponentized pointer X coordinate data and Y coordinate data input to the Y register 17c are input to the AX register 17d and the AY register 17e.
It is adjusted to the exponent part of the 1-dot display accuracy data of the X and Y coordinates input in , and as a result,
The mantissa parts of the X coordinate data and Y coordinate data of the pointers of the X register 17b and Y register 17c are shifted. This is to align the pointer's X and Y coordinate data with the 1-dot display precision data of the X and Y coordinates. In this case, the value of the X register 17b is "9 x 10 ^{- 2} '', Y
The value of the register 17c becomes "0.81×10 ^-2 ".

In the following step S06, the fractions below the decimal point of the mantissa of the values in the X register 17b and Y register 17c are stored in the AX register 17d and AY register 17.
Cleared according to the exponent part of the value of e. This means that X register 17b, Y register 17
The coordinate data of the X and Y coordinates stored in c is
The number of effective digits is determined according to the 1-dot display precision data of the X and Y coordinates input to the AX register 17d and AY register 17e, and here the value of the X register 17b is "9". ×
10 ⁻² ”, and the value of the Y register 17c is “0×10 ⁻² ”.

Since the above processing has completed converting the coordinate data into valid values, the final step is step S07.
Then, the coordinate data of the X and Y coordinates stored in the X register 17b and Y register 17c are read out and sent to the text display buffer 14 as a small number via the arithmetic unit 18. The text display buffer 14 displays the sent X coordinates and Y coordinates.
One of the coordinate data of the coordinates is displayed at the bottom of the display unit 20. The selection between the coordinate data of the X coordinate and the coordinate data of the Y coordinate is performed according to the operation of the "X←→Y" key 11f of the key input unit 11. In this case, the right movement key 11h is operated in sequence. As a result, the characters "X=0.09" and the characters "Y=O" are displayed alternately at the bottom of the display section 20, as shown in FIG. 2a.

Next, the operation when the display range of the graph shown in FIG. 2a is narrowed and the display precision of one dot is increased will be explained. For the graph shown in Figure 2 a above, the range data of the Y coordinate is
Assume that "-0.1" to "0.1" is used to reduce the size to 1/10 and improve display accuracy by 10 times. in this case,
The storage contents of the xmin register 17h and xmax register 17i are "-1", as in the case of FIG. 2a above,
"1", but the stored contents of the ymin register 17j and ymax register 17k are "-0.1", respectively.
It becomes "0.1". x register 17f, y register 1
The memory contents of 7g are both "201" as in the case of FIG. 2a.

Here, in order to display the coordinate data, the process shown in FIG. 3 is performed again. That is, first, in step S01, the coordinate data of the pointer displayed on the graph is calculated. The X coordinate data of this pointer is "0.09" as in FIG. The calculation is performed by substituting the data "y=x ² ", and the calculation result "0.0081" is stored and set in the ymemo register 17m as Y coordinate data.

Next, the process advances to step S02, and the process proceeds to step S02.
The X coordinate data "0.09" of the xmemo register 17 and the Y coordinate data "0.0081" of the ymemo register 17m set in step 1 are each indexed, and as a result, "9×10 ^-2 " is set in the X register 17b.
Input "8.1×10 ^-3 " to each Y register 17c.

Next, as shown in step S03, the display precision for one dot in the X and Y coordinates is calculated and input to the AX register 17d and AY register 17e. In this case, the data stored in the xmax register 17i is "1", the data stored in the xmin register 17h is "-1", and the data stored in the x register 17f is "201", so the calculation is (1-(-1))/ (201-1), the solution "0.01" is input and set in the AX register 17d. Similarly, ymax register 17
Memory data of k is "0.1", ymin register 17j
The stored data is "-0.1" and the stored data in the y register 17g is "201", so by calculation (0.1-(-0.1)/(201-1)), the solution "0.001" is input to the AY register 17e. Set.

After that, in step S04, "0.01" and "0.001" input to the AX register 17d and AY register 17e are converted into exponents, and the AX register 17
Add "1.0×10 ^-2 " to d and AY register 17e.
Set "1.0×10 ^-3 " to

Next, the process advances to step S05, where the X register 17
b, X coordinate data and Y coordinate data of the indexed pointer input to the Y register 17c “9×
10 ^-2 ”, exponent part of “8.1×10 ^-3 ” “10 ^-2 ”, “10 ^-3 ”
is the exponent part "10 -2" of the display precision data "1.0 ^x 10 ^-2 " and "1.0 x 10 ^-3 " for one dot of the X and Y coordinates input to the AX register 17d and AY register 17e, respectively. According to "10 ^-3 ", as a result,
The mantissa parts of the X coordinate data and Y coordinate data of the pointers of the register 17b and Y register 17c are shifted. In this case, the value of the X register 17b is “9×
10 ⁻² ”, and the value of the Y register 17c becomes “8.1×10 ⁻³ ”.

In the following step S06, this register 1
7b, the decimal part of the mantissa of the value in Y register 17c is stored in AX register 17d, AY register 17e.
It is cleared according to the exponent part of the value of (any exponent part smaller than this exponent part is cleared). Here, the value of the X register 17b is cleared from the third decimal place and becomes "9 x 10 ^-2 ", and the value of the Y register 17c is cleared from the fourth decimal place and becomes "8 x 10 ^-3 ". .

Since the above processing has completed converting the coordinate data into valid values, the final step is step S07.
The coordinate data “9×10 ⁻² ” and “8×10 ⁻³ ” stored in the X register 17b and the Y register 17c as valid values of the X coordinate and Y coordinate are read out, and the arithmetic unit 1
8, the decimal numbers "0.09" and "0.008" are sent to the text display buffer 14. The text display buffer 14 displays one of the sent X-coordinate and Y-coordinate data at the bottom of the display section 20. In this case, as shown in FIG. 2b, the display section 2
At the bottom of 0 are the characters “X=0.09” and “Y=
0.008" are displayed alternately by operating the "X←→Y" key 11f.

In this way, the number of valid digits of the displayed pointer coordinate data changes depending on the range data change setting, so that the pointer coordinate data is always displayed with a value that corresponds to the display state of the display unit 20. Become.

[Effects of the invention] As described above, according to this invention, the display accuracy of one dot on the display section is calculated from the range data and the number of display dots, and the coordinate data of the pointer is displayed according to the calculation result. Therefore, 1 of the display section
It is possible to provide a small electronic calculator having a graph display function capable of displaying pointer coordinate data corresponding to the display accuracy of dots.

[Brief explanation of the drawing]

The drawing shows one embodiment of this invention.
2 is a block diagram showing the circuit configuration, FIG. 2 is a diagram showing the display state of the graph and pointer coordinate data on the display section, and FIG. 3 is a flowchart showing the processing contents of coordinate data display. 11...Key input section, 11d...Graph key,
11e...Trace key, 11f..."X←→Y"
key, 11g...Left movement () key, 11h...
Right movement () key, 12... Control section, 13... Graph display buffer, 14... Text display buffer, 15... Pointer control section, 16... Execution pointer, 17... Memory section, 17a... Graph formula Register, 17b...X register, 17c...Y register, 17d...AX register, 17e...
AY register, 17f...X register, 17g...
...Y register, 17h...xmin register, 17
i...xmax register, 17j...ymin register, 17k...ymax register, 17...
xmemo register, 17m...ymemo register,
18... Arithmetic unit, 19... Formula buffer, 20...
...Display section.

Claims (1)

[Scope of utility model registration request] In a small electronic calculator that has a dot matrix display section and has a graph display function that displays a graph and a pointer that moves on the graph line on the display section by inputting a mathematical formula and range data, the display section Accuracy calculation means for calculating the display accuracy of the pointer from the number of dots and the range data; coordinate calculation means for calculating the displayed coordinate position of the pointer according to the display accuracy data by the accuracy calculation means; 1. A small electronic calculator having a graph display function, characterized in that the computer is equipped with coordinate display means for displaying coordinate data obtained by the coordinate calculation means on the display section.