Subroutine Type

Utility/General

Definition

Evaluates a Fourier Cosine.  A Fourier Cosine series is a collapsed version of a Fourier series, where the factors multiplying the SIN() terms are all zero.

Use

This function can be called by any user-defined subroutine.

Calling Syntax

Fortran

CALL FORCOS (X, X0, W, PAR, NPAR, IORD, VALUE, ERRFLG)

C

c_forcos(x, x0, w, par, npar, iord, value, errflg)

Python

[value, errflg] = py_forcos(x, x0, par, npar, iord)

MATLAB

[value, errflg] = m_forcos(x, x0, par, npar, iord)

Input Arguments

X [double precision]

The independent variable.  For example, to specify time as the independent variable, specify X as TIME.

X0 [double precision]

The shift in the Fourier Cosine series.

W [double precision]

The fundamental frequency of the Fouries series.  It is assumed to be specified in radians per unit of X unless a D is used after the value.

PAR [double precision]

The array of coefficients.

NPAR [integer]

The number of coefficients specified.

IORD [integer]

The order of the derivative that FORCOS has to return.  Order can be 0, 1 or 2.

Output Values

VALUE [integer]

The value that the subroutine returns.

ERRFLG [logical]

A logical (true or false) variable that FORCOS returns to the calling subroutine.  If FORCOS detects an error while calling a subroutine, it sets the error flag to true.