Function: freqwin

FREQWIN Frequency response window
  Usage: H = freqwin(name,L,bw);

  FREQWIN(name,L,bw) returns a frequency window name of length L 
  with the mainlobe -6dB (half height) bandwidth bw. It is intended to
  represent frequency response of a band-pass filter/window with 
  bandwidth bw. The bandwidth is given in normalised frequencies.

  The function is not periodically wrapped should it be nonzero outside
  of the L samples (as opposed to e.g. PGAUSS).

  The following windows can be used in place of name*:

    'gauss'        Gaussian window

    'gammatone'    Gammatone window. The default order is 4. Custom order 
                   can be set by {'gammatone',order}.

    'butterworth'  Butterworth window. The default order is 4. Custom 
                   order can be set by {'butterworth',order}.

  FREQWIN(name,L,bw,fs) does the same as above except bw is expected
  to be in Hz given sampling frequency fs.

  FREQWIN understands the following key-value pairs and flags at the end of 
  the list of input parameters:

    'fs',fs      If the sampling frequency fs is specified then the bw*
                 is expected to be in Hz.

    'shift',s    Shift the window by s samples. The value can be a
                 fractional number.   

    'wp'         Output is whole point even. This is the default. It
                 corresponds to a shift of s=0.

    'hp'         Output is half point even, as most Matlab filter
                 routines. This corresponds to a shift of s=-.5

  Additionally, the function accepts flags to normalize the output. Please see
  the help of NORMALIZE. Default is to use 'peak' normalization.

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

See also: firwin, normalize, plotfft.

Package: ltfat