FC_MatrixDeterminant

FC_MatrixDeterminant - General Information

Overview

Type:	Function
Available as of:	V1.0.3.0
Versions:	Current version

Task

Calculates the determinant of a quadratic matrix.

Description

Returns the determinant of a quadratic matrix of the dimension i_diDim x i_diDim. The pointer i_plrMatrix must point to the start of the memory area in which the matrix is stored.

By means of the determinant of a matrix, it is for example, possible to make the following statement on the underlying equation system:

oIf the determinant of the coefficient matrix is not equal to zero, the equation system is clearly solvable.

Interface

Input	Data type	Description
i_diDim	DINT	Line-/ column value of the quadratic matrix. Must be >= 2 .
i_lrZeroLimit	LREAL	Numeric zero limit. Matrix elements that are much smaller than this value are considered as zero. Used to limit the rounding error reproduction. The best value depends on the numeric properties of the matrix. Must be > 0.0. A common value is, e.g. 1E-12.
i_plrMatrix	POINTER TO LREAL	Pointer on the beginning of the memory area in which the matrix is stored, whose determinant has to be calculated.

Output	Data type	Description
q_etDiag	GD.ET_Diag	General library-independent statement on the diagnostic. A value not equal to ET_Diag.Ok corresponds to an diagnostic message.
q_etDiagExt	ET_DiagExt	POU-specific output on the diagnostic. q_etDiag = ET_Diag.Ok -> Status message q_etDiag <> ET_Diag.Ok -> Diagnostic message
q_lrDeterminant	LREAL	Determinant of the quadratic matrix i_plrMatrix.

Output

Data type

Description

q_etDiag

GD.ET_Diag

General library-independent statement on the diagnostic.

A value not equal to ET_Diag.Ok corresponds to an diagnostic message.

q_etDiagExt

ET_DiagExt

POU-specific output on the diagnostic.

q_etDiag = ET_Diag.Ok -> Status message

q_etDiag <> ET_Diag.Ok -> Diagnostic message

q_lrDeterminant

LREAL

Determinant of the quadratic matrix i_plrMatrix.

Notes

oThis function block requires i_diDim * i_diDim * SIZEOF(LREAL) bytes of dynamic memory. Therefore, it must be ensured that the parameter LMCx00C\C\Configuration\Program\DynIECDataSize (total available dynamic memory) is set to an adequate value.

oThe correct size of the storage space that the pointer i_plrMatrix is pointing to (at least i_diDim * i_diDim LREALs) must be carefully checked otherwise the function block causes memory access errors.

oThe function FC_SetMatrixElement() is available for allocating elements of the matrix.

oIf the matrix is give by an array, this can also be allocated directly (without using the previously specified help function). The first index of the array is then the line index of the matrix and the second the gap index.

Diagnostic Messages

q_etDiag	q_etDiagExt	Enumeration value	Description
OK	Ok	0	Ok
ControllerConditionInvalid	DynIecDataSizeTooSmall	75	There is not enough dynamic memory reserved.
InputParameterInvalid	DimRange	72	Dim is outside the valid range.
InputParameterInvalid	PointerMatrixInvalid	69	The pointer Matrix is invalid.
InputParameterInvalid	ZeroLimitRange	74	ZeroLimit is outside the valid range.
UnexpectedProgramBehavior	UnexpectedFeedback	1	An unintended detected error occurred during execution.

DimRange

Enumeration name:	DimRange
Enumeration value:	72
Description:	Dim is outside the valid range.

Issue	Cause	Solution
-	At the input i_diDim, an invalid value has been transferred.	The following must hold: i_diDim > 1

DynIecDataSizeTooSmall

Enumeration name:	DynIecDataSizeTooSmall
Enumeration value:	75
Description:	There is not enough dynamic memory reserved.

Issue	Cause	Solution
-	There is no or not enough dynamic memory available.	Increase the available dynamic memory Controller > Configuration > IEC-Program > DynIECDataSize.

Enumeration name:	Ok
Enumeration value:	0
Description:	Ok

The determinant has been calculated successfully

PointerMatrixInvalid

Enumeration name:	PointerMatrixInvalid
Enumeration value:	69
Description:	The pointer Matrix is invalid.

Issue	Cause	Solution
-	At the input i_plrXMatrix, a null pointer has been transferred.	At the input i_plrXMatrix, the address of the memory containing the matrix must be transferred.

UnexpectedFeedback

Enumeration name:	UnexpectedFeedback
Enumeration value:	1
Description:	An unintended detected error occurred during execution.

Issue	Cause	Solution
-	An error occurred in the internal execution.	Please inform the support team about this error.

ZeroLimitRange

Enumeration name:	ZeroLimitRange
Enumeration value:	74
Description:	ZeroLimit is outside the valid range.

Issue	Cause	Solution
-	At the input i_lrZeroLimit, a number <= 0 has been applied.	i_lrZeroLimit must be greater than 0.