Function: frsynmatrix
FRSYNMATRIX  Frame synthesis operator matrix
  Usage: G=frsynmatrix(F,L);

  G=FRSYNMATRIX(F,L) returns the matrix representation G of the frame
  synthesis operator for a frame F of length L. The frame object F*
  must have been created using FRAME.

  The frame synthesis operator matrix contains all the frame atoms as
  column vectors. It has dimensions L xNcoef, where Ncoef is the
  number of coefficients. The number of coefficients can be found as
  Ncoef=frameclength(L). This means that the frame matrix is usually
  *very* large, and this routine should only be used for small values of
  L.

  The action of the frame analysis operator FRANA is equal to
  multiplication with the Hermitean transpose of the frame synthesis
  matrix. Consider the following simple example:

    L=200;
    F=frame('dgt','gauss',10,20);
    G=frsynmatrix(F,L);
    testsig = randn(L,1);
    res = frana(F,testsig)-G'*testsig;
    norm(res)
    % Show the matrix (real and imaginary parts)
    figure(1); imagesc(real(G));
    figure(2); imagesc(imag(G));

Url: http://ltfat.github.io/doc/frames/frsynmatrix.html

See also: frame, frana, frsyn.

Package: ltfat