Public – Campbell Scientific CR5000 Measurement and Control Module User Manual

Page 90

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Section 5. Program Declarations

5-2

Const Declaration Example

The example uses Const to define the symbolic constant PI.

Const PI = 3.141592654

'Define constant.

Dim Area, Circum, Radius

'Declare variables.

Radius = Volt( 1 )

'Get measurement.

Circum = 2 * PI * Radius

'Calculate circumference.

Area = PI * ( Radius ^ 2 )

'Calculate area.

Dim

Declares variables and allocates storage space. In CRBasic, ALL variables MUST
be declared.

Syntax

Dim

varname[([subscripts]) [, varname[([subscripts])]]

Remarks
The Dim statement has these parts:

Part

Description

varname

Name of a variable.

subscripts

Dimensions of an array variable. You can declare multiple
dimensions.

The argument subscripts has the following syntax:
size [size, size]

In CRBasic the Option Base is always 1. This means the lowest number in a
dimension is 1 and not 0.

Dim A( 8, 3 )

The maximum number of array dimensions allowed in a Dim statement is 3. If a
program uses a subscript that is greater than the dimensioned value, a subscript out
of bounds error is recorded.

When variables are initialized, they are initialized to 0

Tip

Put Dim statements at the beginning of the program.

Public

Dimensions a variable as public and available in the Public table of the CR5000.

Syntax

Public(

list of [dimensioned] variables that make up the Public Table

)

Remarks
More than one Public statement can be made.

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