*MFOURI

*MFOURI, Oper, COEFF, MODE, ISYM, THETA, CURVE
Calculates the coefficients for, or evaluates, a Fourier series.

APDL: Array Parameters

Argument Descriptions

Oper

Type of Fourier operation:

FIT --: Calculate Fourier coefficients COEFF from MODE, ISYM, THETA, and CURVE.
EVAL --: Evaluate the Fourier curve CURVE from COEFF, MODE, ISYM andTHETA

COEFF

Name of the array parameter vector containing the Fourier coefficients (calculated if Oper = FIT, required as input if Oper = EVAL). See *SET for name restrictions.

MODE

Name of the array parameter vector containing the mode numbers of the desired Fourier terms.

ISYM

Name of the array parameter vector containing the symmetry key for the corresponding Fourier terms. The vector should contain keys for each term as follows:

0 or 1 --: Symmetric (cosine) term
-1 --: Antisymmetric (sine) term.

THETA, CURVE

Names of the array parameter vectors containing the theta vs. curve description, respectively. Theta values should be input in degrees. If Oper = FIT, one curve value should be supplied with each theta value. If Oper = EVAL, one curve value will be calculated for each theta value.

Notes

Calculates the coefficients of a Fourier series for a given curve, or evaluates the Fourier curve from the given (or previously calculated) coefficients. The lengths of the COEFF, MODE, and ISYM vectors must be the same--typically two times the number of modes desired, since two terms (sine and cosine) are generally required for each mode. The lengths of the CURVE and THETA vectors should be the same or the smaller of the two will be used. There should be a sufficient number of points to adequately define the curve--at least two times the number of coefficients. A starting array element number (1) must be defined for each array parameter vector. The vector specifications *VLEN, *VCOL, *VABS, *VFACT, and *VCUM do not apply to this command. Array elements should not be skipped with the *VMASK and the NINC value of the *VLEN specifications. The vector being calculated (COEFF if Oper is FIT, or CURVE if Oper is EVAL) must exist as a dimensioned array [*DIM].

This command is valid in any processor.

Menu Paths

Utility Menu>Parameters>Array Operations>Matrix Fourier