c = xcorr(a,b,shape) : computes the correlation of iData objects
@iData/xcorr function to compute the correlation of data sets (FFT based).
A decorrelation mode is also possible with e.g.
shape='same center deconv' or shape='same center iter'.
When only one argument is given, the auto-correlation is computed.
input: a: object or array (iData or numeric)
b: object or array (iData or numeric)
shape: optional shape of the return value
full Returns the full two-dimensional correlation.
same Returns the central part of the correlation of the same size as a.
valid Returns only those parts of the correlation that are computed
without the zero-padded edges. Using this option, y has size
[ma-mb+1,na-nb+1] when all(size(a) >= size(b)).
deconv Performs an FFT deconvolution.
deconv_iter Performs an iterative deconvolution.
pad Pads the 'a' signal by replicating its starting/ending values
in order to minimize the correlation side effects
center Centers the 'b' filter so that correlation does not shift
the 'a' signal.
normalize Normalizes the 'b' filter so that the correlation does not
change the 'a' signal integral.
background Remove the background from the filter 'b' (subtracts the minimal value)
Default shape is 'same center'
output: c: object or array (iData)
ex: c=xcorr(a,b); c=xcorr(a,b, 'same pad background center normalize');
Version: Nov. 26, 2018
See also iData, iData/times, iData/convn, iData/fft, convn, fconv, fconvn