Filter Design Toolbox

qfft

Construct a quantized FFT

Syntax

• f = qfft
  f = qfft('propertyname1',propertyvalue1, ...)
  f = qfft(a)
  f = qfft(pn,pv)
  

f = qfft('quantize',[14 13])

Description

f = qfft creates a quantized FFT with default property values.

f = qfft('propertyname1',propertyvalue1,...) uses property name/ property value pairs to set the properties of the quantized FFT.

f = qfft(a), where a is a structure whose field names are quantized FFT property names, sets the properties named in each field name to the values contained in the structure.

f = qfft(pn,pv) sets the quantized FFT properties specified in the cell array of strings pn to the corresponding property values in cell array pv.

f = qfft('quantize',[14 13]) sets all data format properties for the quantized FFT to the same word length and fraction length.

Refer to A Quick Guide to Quantized FFT Properties for a list of quantized FFT properties.

Examples

Create a quantized FFT f and apply it to a data set. Plot the result.

• warning on
  n=128;
  t = (1:n)/n;
  x = sin(2*pi*10*t)/10;
  f = qfft('length',n);
  plot(t,abs([fft(f,x);fft(x)]))
  

See Also
fft, get, ifft, qreport, set

order

qfilt