Campbell CR800 Series, Руководство оператора

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Section 7. Installation
159
Caution Concerning characters allowed in names, characters not listed
in in the table,
Rules for Names
, may appear to be supported in a specific
operating system. However, they may not be supported in future
operating systems.
Rules for Names
Name
Category
1
Maximum
Length
(number of
characters)
Allowed characters
Variable or array 39
Letters A to Z, a to z, _ (underscore),
and numbers 0 to 9. Names must start
with a letter or underscore. CRBasic
is not case sensitive.
Units are excepted from the above
rules. Since units are strings that ride
along with the data, they are not
subjected to the stringent syntax
checking that is applied to variables,
constants, subroutines, tables, and
other names.
Constant 38
Units 38
Alias 39
Station name 64
Data-table name 20
Field name 39
Field-name
description
64
1
Variables, constants, units, aliases, station names, field names, data table
names, and file names can share identical names; that is, once a name is used,
it is reserved only in that category. See Predefined Constants
(p. 138)
for another
naming limitation.
7.6.3.15 Expressions in Arguments
Read More See
Programming Expression Types
(p. 160).
Many CRBasic instruction parameters allow the entry of arguments as
expressions. If an expression is a comparison, it will return -1 if true and 0 if false.
See Logical Expressions
(p. 163).
The following code snip shows the use of an
expressions as an argument in the TrigVar parameter of the DataTable()
instruction: