Filter Design Toolbox

isreal

Test quantized filters for purely real coefficients

Syntax

• r = isreal(hq)
  

Description

r = isreal(hq) returns r = 1 (or true) if all reference filter coefficients for the quantized filter hq are real, and returns r = 0 (or false) otherwise.

isreal(hq) returns 1 if all filter coefficients in quantized filter hq have zero imaginary part. Otherwise, isreal(hq) returns a 0 indicating that the filter is complex. Complex quantized filters have one or more coefficients with nonzero imaginary parts.

Note    Quantizing a filter cannot make a real filter into a complex filter.

Examples

• % Create a reference filter.
  [b,a] = ellip(2,0.5,20,0.4); 
  
  % Create a quantized filter from the reference filter.
  
  hq = qfilt('df2t',{b,a});
  
  % Test if all filter coefficients are real.
  
  r = isreal(hq)
  
  r =
       1
  

See Also
isfir, islinphase, ismaxphase, isminphase, issos, isstable, isallpass

isminphase

issos