Malvern Instruments Zetasizer 1000, Basic Reference Manual

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2.1 Introduction
The program language used in the Zetasizer software is similar to many other variants of Basic.
Some features of other versions are not needed for our application and many extra functions
have been added for specific use in particle sizing.
Throughout these notes the term Basic will
mean the specific Malvern Zetasizer version of the language.
Basic is a line interpreted language. This means that as a program is executed each line is
checked for syntax and then executed. Unless controlled to do otherwise, the execution will
continue with the next line.
This means that, when you test a program, an error some way down
the program will not be reported until you reach that line.
Zetasizer Basic program examples in the manual are shown in the
Courier
font.
The fundamental building block of a program is the statement. This is a single instruction to
perform some action. A line in the program may contain more than one statement. Any statements
on a line must be separated by colons (:
).
For example :
X = 3 : Y = 2 : Z =-5
and
X = 3
Y = 2
Z =-5
are equivalent.
The lines of a program may be labeled. This is not necessary except when you need to refer to
a specific line from within the program itself.
The apostrophe character ( ‘ ) is used to mark comments. Any line beginning with this character
is ignored when the program is executed. Comments may be added at the end of lines using the
same character.
For example :
‘Area of a rectangle
‘Prompt for length’
10 Input “Input length”, Rectlength
‘Prompt for width’
Input “Input width” Rectwidth
‘ Calculate area
RectArea = RectLength * RectWidth
Print dialogue, Using, “####.##”, RectArea
GoTo 10
Notice the following :
l The use of comments.
Introduction to Zetasizer basic MAN 0179
Page 2.1
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