Campbell Scientific CR6 CR6 Measurement and Control System - Page 135

CRBasic Example 6., Using a Variable Array in Calculations

Page 135 highlights

Section 7. Installation Arrays • $ 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 value. Public SetTemp = {35} In string variables, string size defaults to 24 characters. 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 variable name that 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 simply declare a variable array as shown below: Public TempC(4), This creates in memory the four variables TempC(1), TempC(2), TempC(3), and TempC(4). A variable array is useful in program operations that affect many variables in the same way. CRBasic example Using a Variable Array in Calculations (p. 135) shows code that uses a variable array to reduce the code required to convert four temperatures from Celsius degrees to Fahrenheit degrees. In this example, a For/Next structure with a changing variable is used to specify which elements of the array will have the logical operation applied to them. The CRBasic For/Next function will only operate on array elements that are clearly specified and ignore the rest. If an array element is not specifically referenced, as is the case in the following declaration, Dim TempC() CRBasic references only the first element of the array, TempC(1). CRBasic Example 6. Using a Variable Array in Calculations ' the use of a variable array to reduce code. In this 'example, two variable arrays are used to convert four temperature measurements from 'degree C to degrees F. Public TempC(4) Public TempF(4) Dim T 135

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Section 7.
Installation
$
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 value.
Public SetTemp = {35}
In string variables, string size defaults to 24 characters.
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 variable
name that 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
simply declare a variable array as shown below:
Public
TempC(4),
This creates in memory the four variables TempC(1), TempC(2), TempC(3), and
TempC(4).
A variable array is useful in program operations that affect many variables in the
same way.
CRBasic example
Using a Variable Array in Calculations
(p. 135)
shows code that uses a variable array to reduce the code required to convert four
temperatures from Celsius degrees to Fahrenheit degrees.
In this example, a
For/Next
structure with a changing variable is used to specify
which elements of the array will have the logical operation applied to them.
The
CRBasic
For/Next
function will only operate on array elements that are clearly
specified and ignore the rest.
If an array element is not specifically referenced, as
is the case in the following declaration,
Dim TempC()
CRBasic references only the first element of the array,
TempC(1)
.
CRBasic Example 6.
Using a Variable Array in Calculations
'<TPED> the use of a variable array to reduce code.
In this
'example, two variable arrays are used to convert four temperature measurements from
'degree C to degrees F.
Public
TempC(4)
Public
TempF(4)
Dim
T
135