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comparison scripts/signal/fftconv.m @ 3426:f8dde1807dee

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[project @ 2000-01-13 08:40:00 by jwe]
author jwe
date Thu, 13 Jan 2000 08:40:53 +0000
parents 0748b03c3510
children 858695b3ed62
comparison
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3425:8625164a0a39 3426:f8dde1807dee
21 ## @deftypefn {Function File} {} fftconv (@var{a}, @var{b}, @var{n}) 21 ## @deftypefn {Function File} {} fftconv (@var{a}, @var{b}, @var{n})
22 ## Return the convolution of the vectors @var{a} and @var{b}, as a vector 22 ## Return the convolution of the vectors @var{a} and @var{b}, as a vector
23 ## with length equal to the @code{length (a) + length (b) - 1}. If @var{a} 23 ## with length equal to the @code{length (a) + length (b) - 1}. If @var{a}
24 ## and @var{b} are the coefficient vectors of two polynomials, the returned 24 ## and @var{b} are the coefficient vectors of two polynomials, the returned
25 ## value is the coefficient vector of the product polynomial. 25 ## value is the coefficient vector of the product polynomial.
26 ## 26 ##
27 ## The computation uses the FFT by calling the function @code{fftfilt}. If 27 ## The computation uses the FFT by calling the function @code{fftfilt}. If
28 ## the optional argument @var{n} is specified, an N-point FFT is used. 28 ## the optional argument @var{n} is specified, an N-point FFT is used.
29 ## @end deftypefn 29 ## @end deftypefn
30 30
31 ## Author: KH <Kurt.Hornik@ci.tuwien.ac.at> 31 ## Author: KH <Kurt.Hornik@ci.tuwien.ac.at>
51 b(lc) = 0; 51 b(lc) = 0;
52 if (nargin == 2) 52 if (nargin == 2)
53 c = fftfilt (a, b); 53 c = fftfilt (a, b);
54 else 54 else
55 if !(is_scalar (N)) 55 if !(is_scalar (N))
56 error ("fftconv: N has to be a scalar"); 56 error ("fftconv: N has to be a scalar");
57 endif 57 endif
58 c = fftfilt (a, b, N); 58 c = fftfilt (a, b, N);
59 endif 59 endif
60 endif 60 endif
61 61