Graphics function, Substrings – VTech Precomputer Power Pad Plus User Manual

Page 58

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VAL

VAL works like STR$ but in reverse. It changes a string argument into a number. Look
at the following short program.

Example:

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A$=“33”

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B$=“20”

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C=VAL(A$+B$)

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D= VAL (A$) + VAL (B$)

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PRINT C;D

RUN

3320 53

GRAPHICS FUNCTION

PGET function

Returns the color attribute of a specified pixel.

PGET(X, Y) = n

n

Returns

1

the current coordinates(X, Y) turns the pixel status ON

0

the current coordinates(X, Y) turns the pixel status OFF

SUBSTRINGS

It is also possible to get substrings of strings. A substring is a part of a string. For example:
“ABC” is a substring of “ABCDE”. The following three functions operate on substrings.

LEFT$ (A$,N)

This will return the substring from the left-most of string A$, the first character to the Nth
character.

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