Campbell CR850, Руководство оператора

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Section 7. Installation
118
CRBasic Example 8. Using Variable Array Dimension Indices
Dim aaa As Long
Dim bbb As Long
Dim ccc As Long
Public VariableName(4,4,4) As Float
BeginProg
Scan ()
aaa = 3
bbb = 2
ccc = 4
VariableName(aaa,bbb,ccc) = 2.718
NextScan
EndProg
Dimensioning Strings
Strings can be declared to a maximum of two dimensions. The third "dimension"
is used for accessing characters within a string. See
String Operations
(p. 237).
String length can also be declared.
A one-dimension string array called StringVar , with five elements in the array
and each element with a length of 36 characters, is declared as
Public StringVar(5) As String * 36
Five variables are declared, each 36 characters long:
StringVar(1)
StringVar(2)
StringVar(3)
StringVar(4)
StringVar(5)
Data Types
Variables and stored data can be configured with various data types to optimize
program execution and memory usage.
The declaration of variables (via the Dim or Public instructions) allows an
optional type descriptor As that specifies the data type. The default data type,
without a descriptor, is IEEE4 floating point ( As FLOAT ). Variable data types
are As String and three numeric types: As Float , As Long , and As Boolean.
Stored data has additional data type options FP2 , UINT2 , BOOL8 , and NSEC .
CRBasic example Data Type Declarations
(p. 120)
shows these in use in the
declarations and output sections of a CRBasic program.
The CRBasic programming language allows mixing data types within a single
array of variables; however, this practice can result in at least one problem. The
datalogger support software is incapable of efficiently handling different data
types for the same field name. Consequently, the software mangles the field
names in data file headers.
Table Data Types
(p. 119)
lists details of available data types.