Campbell Scientific CR1000KD CR800 and CR850 Measurement and Control Systems - Page 116

Single-Line Declarations

Page 116 highlights

Section 7. Installation 7.7.3.4 Single-Line Declarations Public, Dim, and ReadOnly variables are declared at the beginning of a CRBasic program, as are Constants, Units, Aliases, StationNames, DataTables, and Subroutines. Table Rules for Names (p. 140) lists declaration names and allowed lengths. 7.7.3.4.1 Variables A variable is a packet of memory given an alphanumeric name through which pass measurements and processing results during program execution. Variables are declared either as Public or Dim at the discretion of the programmer. Public variables can be viewed through the external keyboard / display or software numeric monitors. Dim variables cannot. All user defined variables are initialized once when the program starts. Additionally, variables that are used in the Function() or Sub() declaration,or that are declared within the body of the function or subroutine are local to that function or subroutine. Variable names can be up to 39 characters in length, but most variables should be no more than 35 characters long. This allows for four additional characters that are added as a suffix to the variable name when it is output to a data table. Variable names can contain the following characters: • A to Z • a to z • 0 to 9 • _ (underscore) • $ Names must start with a letter, underscore, or dollar sign. Spaces and quote marks are not allowed. Variable names are not case sensitive. Several variables can be declared on a single line, separated by commas: Public RefTemp, AirTemp2, Batt_Volt Variables can also be assigned initial values in the declaration. Following is an example of declaring a variable and assigning it an initial valued. Public SetTemp = {35} In string variables, string size defaults to 24 characters (changed from 16 characters in April 2013, OS 26). Arrays When a variable is declared, several variables of the same root name can also be declared. This is done by placing a suffix of "(x)" on the alphanumeric name, which creates an array of x number of variables that differ only by the incrementing number in the suffix. For example, rather than declaring four similar variables as follows, Public TempC1 Public TempC2 Public TempC3 Public TempC4 116

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Section 7.
Installation
116
7.7.3.4 Single-Line Declarations
Public
,
Dim
, and
ReadOnly
variables are declared at the beginning of a CRBasic
program, as are
Constant
s,
Units
,
Alias
es,
StationName
s,
DataTable
s, and
Subroutine
s.
Table
Rules for Names
(p. 140)
lists declaration names and allowed
lengths.
7.7.3.4.1 Variables
A variable is a packet of memory given an alphanumeric name through which
pass measurements and processing results during program execution. Variables
are declared either as
Public
or
Dim
at the discretion of the programmer.
Public
variables can be viewed through the external keyboard / display or software
numeric monitors.
Dim
variables cannot.
All user defined variables are initialized once when the program starts.
Additionally, variables that are used in the
Function()
or
Sub()
declaration,or that
are declared within the body of the function or subroutine are local to that
function or subroutine.
Variable names can be up to 39 characters in length, but most variables should be
no more than 35 characters long.
This allows for four additional characters that
are added as a suffix to the variable name when it is output to a data table.
Variable names can contain the following characters:
A to Z
a to z
0 to 9
_ (underscore)
$
Names must start with a letter, underscore, or dollar sign.
Spaces and quote
marks are not allowed.
Variable names are not case sensitive.
Several variables can be declared on a single line, separated by commas:
Public RefTemp, AirTemp2, Batt_Volt
Variables can also be assigned initial values in the declaration.
Following is an
example of declaring a variable and assigning it an initial valued.
Public SetTemp = {35}
In string variables, string size defaults to 24 characters (changed from 16
characters in April 2013, OS 26).
Arrays
When a variable is declared, several variables of the same root name can also be
declared. This is done by placing a suffix of "(x)" on the alphanumeric name,
which creates an array of x number of variables that differ only by the
incrementing number in the suffix. For example, rather than declaring four similar
variables as follows,
Public
TempC1
Public
TempC2
Public
TempC3
Public
TempC4