FC_FourierPartialSum

FC_FourierPartialSum - General Information

Overview

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

Task

This calculates a Fourier partial sum.

Description

This calculates the value of a finite Fourier partial sum. The requirement for this is that first the Fourier coefficients have been calculated up to a sufficiently large index, using the function FC_FourierCoefficients.

The Fourier partial sum for function f up to the index N has the following form (with regard to the definition of the Fourier coefficients see FC_FourierCoefficients):

Under suitable preconditions for the function f, S _{f, N} approximates the latter as well as required for a sufficiently large N.

Interface

Input	Data type	Description
i_lrXPeriod	LREAL	Period of the function / length of the definition range
i_diMaxIndex	DINT	Index up to which the Fourier partial sum is to be calculated (designated above as N ). The Fourier coefficients must first have been calculated at least up to this index, using the function FC_FourierCoefficients.
i_plrFourierCoefficientsA	POINTER TO LREAL	Pointer to the start of the array with Fourier coefficients A, which first have been calculated using the function FC_FourierCoefficients.
i_plrFourierCoefficientsB	POINTER TO LREAL	Pointer to the start of the array with Fourier coefficients B, which first have been calculated using the function FC_FourierCoefficients.
i_lrXValue	LREAL	X value for which the Fourier partial sum is 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_lrFourierPartialSum	LREAL	Calculated value of the Fourier partial sum at the point i_lrXValue.

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_lrFourierPartialSum

LREAL

Calculated value of the Fourier partial sum at the point i_lrXValue.

Diagnostic Messages

q_etDiag	q_etDiagExt	Enumeration value	Description
OK	Ok	0	Ok
InputParameterInvalid	MaxIndexRange	61	MaxIndex is outside the valid range.
InputParameterInvalid	PointerFourierCoefficientsAInvalid	62	The pointer VourierCoefficientsA is invalid.
InputParameterInvalid	PointerFourierCoefficientsBInvalid	63	The pointer VourierCoefficientsB is invalid.
InputParameterInvalid	XPeriodRange	58	XPeriod is outside the valid range.

MaxIndexRange

Enumeration name:	MaxIndexRange
Enumeration value:	61
Description:	MaxIndex is outside the valid range.

Issue	Cause	Solution
-	At the input i_diMaxIndex, an invalid value has been applied.	At the input i_diMaxIndex, a value greater than or equal to 0 must be transferred.

Enumeration name:	Ok
Enumeration value:	0
Description:	Ok

The partial sum has been calculated successfully.

PointerFourierCoefficientsAInvalid

Enumeration name:	PointerFourierCoefficientsAInvalid
Enumeration value:	62
Description:	The pointer VourierCoefficientsA is invalid.

Issue	Cause	Solution
-	At the input i_plrFourierCoefficientsA, an invalid value has been applied.	At the input i_plrFourierCoefficientsA, a value not equal to 0 must be transferred.

PointerFourierCoefficientsBInvalid

Enumeration name:	PointerFourierCoefficientsBInvalid
Enumeration value:	63
Description:	The pointer VourierCoefficientsB is invalid.

Issue	Cause	Solution
-	At the input i_plrFourierCoefficientsB, an invalid value has been applied.	At the input i_plrFourierCoefficientsB, a value not equal to 0 must be transferred.

XPeriodRange

Enumeration name:	XPeriodRange
Enumeration value:	58
Description:	XPeriod is outside the valid range.

Issue	Cause	Solution
-	At the input i_lrXPeriod, a number smaller than Gc_lrZeroTolerance has been applied.	i_lrXPeriod must be greater than 0.