%StructCalcOp function

Function

The function performs a given mathematical operation over a part of local structures. This function belongs to the control functions.

Declaration

%StructCalcOp(
       in _recA[fromRowA]^fromColA, IN _recA[toRowA]^toColA,
       in  _recB[fromRowB]^fromColB,
       in _recC[fromRowC]^fromRowC,
   INT in _operation [, IN BOOL _bInvalidIsZero = @TRUE],
 )

Parameters

_recA[fromRowA]^fromColA, _recA[toRowA]^toColA	Reference to the value of local structured variable field.
_recB[fromRowB]^fromColB	Reference to the value of local structured variable field.
_recC[fromRowC]^fromRowC	Reference to the value of local structured variable field.
INT IN _operation	Type of performed mathematical operation.
IN BOOL _bInvalidIsZero	Optional parameter. Determines a behavior of mathematical operation in case that some of operands has an invalid value.

Description

The value of parameter _operation determines the mathematical operation according to this table:

Value	Mathematical operation
0	+
1	-
2	*
3	/

The mathematical operation is performed as follows:

C = A + B

where:
Symbol A represents an area of local structured variable values which is given by its left upper corner (field _recA[fromRowA]^fromColA) and right lower corner (field _recA[toRowA]^toColA). The structured variable which is used in the first and second parameter must be the same. The dimensions (number of rows and columns) are also defined by this way. They are used in definition of B and C areas that are defined only by their right upper corner in the parameters.
The mathematical operation (defined by parameter) is performed among the individual appropriate fields of A and B areas. A result is written into area C.
A set parameter _bInvalidIsZero (zeroing of invalid value) is interpreted as follows:

using the operators + and -, the invalid values are, before a calculation, considered as zero values
using the operators * and /, the result is 0

Example

In following example there is shown an addition of two matrixes.
The first matrix is delimited by fields _A[1]^_firstColNr (where _firstColNr has value =1) and _A[2]^_lastColNr (where _lastColNr is set on consecutive number of the last column of relevant structure).
The second matrix is defined by the field _B[1]^_firstColNr and consists of two rows and of the same number of columns like matrix in variable _A.
The result is written to appropriate fields in variable _C.

 BEGIN
  RECORD (SD.BIG) _A
  RECORD (SD.BIG) _B
  RECORD (SD.BIG) _C
 
  REDIM _A[20]
  REDIM _B[20]
  REDIM _C[20]
 
 INT _firstColNr, _lastColNr 
 
 _firstColNr := 1
 _lastColNr := _A\CNR
 _A[1]^R1 := 1
 _A[2]^R1 := 2
 _B[1]^R1 := 1
 _B[2]^R1 := 2
 %StructCalcOp(_A[1]^_firstColNr,_A[2]^_lastColNr,_B[1]^_firstColNr,_C[1]^_firstColNr,0)
 
 END