Function: dgtlength
DGTLENGTH  DGT length from signal
  Usage: L=dgtlength(Ls,a,M);
         L=dgtlength(Ls,a,M,lt);

  DGTLENGTH(Ls,a,M) returns the length of a Gabor system that is long
  enough to expand a signal of length Ls. Please see the help on
  DGT for an explanation of the parameters a and M.

  If the returned length is longer than the signal length, the signal
  will be zero-padded by DGT.

  A valid transform length must be divisable by both a and M. This
  means that the minumal admissable transform length is :

    Lsmallest = lcm(a,M);

  and all valid transform lengths are multipla of Lsmallest*

  Non-separable lattices:
  -----------------------

  DGTLENGTH(Ls,a,M,lt) does as above for a non-separable lattice with
  lattice-type lt. For non-separable lattices, there is the additinal
  requirement on the transform length, that the structure of the
  lattice must be periodic. This gives a minimal transform length of :

    Lsmallest = lcm(a,M)*lt(2);

Url: http://ltfat.github.io/doc/gabor/dgtlength.html

See also: dgt.

Package: ltfat