28 lines
825 B
Matlab
28 lines
825 B
Matlab
function cdf = gamm_cdf (x, a)
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% PURPOSE: returns the cdf at x of the gamma(a) distribution
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%---------------------------------------------------
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% USAGE: cdf = gamm_cdf(x,a)
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% where: x = a vector
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% a = a scalar gamma(a)
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%---------------------------------------------------
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% RETURNS:
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% a vector of cdf at each element of x of the gamma(a) distribution
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% --------------------------------------------------
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% SEE ALSO: gamm_d, gamm_pdf, gamm_rnd, gamm_inv
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%---------------------------------------------------
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% Anders Holtsberg, 18-11-93
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% Copyright (c) Anders Holtsberg
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if nargin ~= 2
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error('Wrong # of arguments to gamm_cdf');
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end;
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if any(any(a<=0))
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error('gamm_cdf: parameter a is wrong')
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end
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cdf = gammainc(x,a);
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I0 = find(x<0);
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cdf(I0) = zeros(size(I0));
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