WTRAYLCDF Truncated Rayleigh cumulative distribution function CALL: F = wtraylcdf(x,b,c); F = distribution function evaluated at x b = scale parameter c = truncation parameter (default 0) The truncated Rayleigh distribution is defined by its cdf F(x;b,c) = 1 - exp(-(x-c)^2/(2b^2)+c^2/(2b^2)), x>=0 Example: x = linspace(0,4,200); p1 = wtraylcdf(x,1); p2 = wtraylcdf(x,0.5,-2); plot(x,p1,x,p2)
Check if all input arguments are either scalar or of common size. | |
Display message and abort function. | |
Not-a-Number. |
Parameter estimates for Truncated Rayleigh data. |
001 function F = wraylcdf(x,b,c,a); 002 %WTRAYLCDF Truncated Rayleigh cumulative distribution function 003 % 004 % CALL: F = wtraylcdf(x,b,c); 005 % 006 % F = distribution function evaluated at x 007 % b = scale parameter 008 % c = truncation parameter (default 0) 009 % The truncated Rayleigh distribution is defined by its cdf 010 % 011 % F(x;b,c) = 1 - exp(-(x-c)^2/(2b^2)+c^2/(2b^2)), x>=0 012 % 013 % Example: 014 % x = linspace(0,4,200); 015 % p1 = wtraylcdf(x,1); p2 = wtraylcdf(x,0.5,-2); 016 % plot(x,p1,x,p2) 017 018 % Reference: Cohen & Whittle, (1988) "Parameter Estimation in Reliability 019 % and Life Span Models", p. 181 ff, Marcel Dekker. 020 021 022 % Tested on: Matlab 5.3 023 % History: 024 % by pab 03.12.2000 025 % based on wraylpdf 026 027 error(nargchk(2,4,nargin)) 028 if nargin<3|isempty(c),c=0;end 029 if nargin<4|isempty(a),a=2;end 030 [errorcode, x, b,c] = comnsize (x,b,c); 031 if (errorcode > 0) 032 error ('x, b and c must be of common size or scalar'); 033 end 034 035 F = zeros(size(x)); 036 037 k = find ((x>=0)&(b>0)); 038 039 if any(k) 040 F(k)=(1-exp(-(x(k)-c(k)).^a./(2*b(k).^a)+abs(c(k)).^a./(2*b(k).^a))); 041 end 042 043 k1 = find (b<=0); 044 if any(k1) 045 tmp=NaN; 046 F(k1) = tmp(ones(size(k1))); 047 end 048 049 050 051 052
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