The ifourier function applies the inverse Fourier transform to M using the definition

The ifourier(M) calling sequence computes the element-wise inverse Fourier transform of M.  The result, R, is formed as R[i,j] = ifourier(M[i,j], v, u).

ifourier(F) is the inverse Fourier transform of the scalar F with default independent variable w.  If F is not a function of w, then F is  assumed to be a function of the independent variable returned by findsym(F,1). By default, the return value is a function of x.

If F = F(x), then ifourier returns a function of t. The integration above proceeds with respect to w.

ifourier(F,u) makes F a function of the variable u instead of the default x. The integration above proceeds with respect to w.

ifourier(F,v,u) takes F to be a function of v instead of the default w. The integration is then with respect to v.