Function: pfilt
PFILT  Apply filter with periodic boundary conditions
  Usage:  h=pfilt(f,g);
          h=pfilt(f,g,a,dim);

  PFILT(f,g) applies the filter g to the input f. If f is a
  matrix, the filter is applied along each column.

  PFILT(f,g,a) does the same, but downsamples the output keeping only
  every a'th sample (starting with the first one).

  PFILT(f,g,a,dim) filters along dimension dim. The default value of
  [] means to filter along the first non-singleton dimension.

  The filter g can be a vector, in which case the vector is treated
  as a zero-delay FIR filter.

  The filter g can be a cell array. The following options are
  possible:

     If the first element of the cell array is the name of one of the
      windows from FIRWIN, the whole cell array is passed onto
      FIRFILTER.

     If the first element of the cell array is 'bl', the rest of the
      cell array is passed onto BLFILTER.

     If the first element of the cell array is 'pgauss', 'psech',
      the rest of the parameters is passed onto the respective
      function. Note that you do not need to specify the length L.

  The coefficients obtained from filtering a signal f by a filter g are
  defined by

              L-1
     c(n+1) = sum f(l+1) * g(an-l+1)
              l=0

  where an-l is computed modulo L.

Url: http://ltfat.github.io/doc/sigproc/pfilt.html

See also: pconv.

Package: ltfat