WBETACDF Beta cumulative distribution function CALL: F = wbetacdf(x,a,b); F = distribution function evaluated at x x = matrix a,b = distribution parameters It is defined by its PDF: f = x^(a-1)*(1-x)^(b-1)/H(a,b) 0<= x <= 1, a>0, b>0 where H(a,b) is a normalization constant. Example: x = linspace(0,1,200); p1 = wbetacdf(x,1,1); p2 = wbetacdf(x,2,2); plot(x,p1,x,p2)
Check if all input arguments are either scalar or of common size. | |
Incomplete beta function. | |
Display message and abort function. | |
Not-a-Number. |
Beta Rayleigh CDF of wave heights | |
Parameter estimates for Beta data. | |
Inverse of the Beta distribution function | |
Snedecor's F cumulative distribution function |
001 function F = wbetacdf(x,a,b) 002 %WBETACDF Beta cumulative distribution function 003 % 004 % CALL: F = wbetacdf(x,a,b); 005 % 006 % F = distribution function evaluated at x 007 % x = matrix 008 % a,b = distribution parameters 009 % 010 % It is defined by its PDF: 011 % 012 % f = x^(a-1)*(1-x)^(b-1)/H(a,b) 0<= x <= 1, a>0, b>0 013 % 014 % where H(a,b) is a normalization constant. 015 % 016 % Example: 017 % x = linspace(0,1,200); 018 % p1 = wbetacdf(x,1,1); p2 = wbetacdf(x,2,2); 019 % plot(x,p1,x,p2) 020 021 % tested on matlab 5.3 022 %History: 023 %revised pab 29.10.2000 024 % adapted from stixbox 025 % -added nargchk, comnsize 026 % Anders Holtsberg, 18-11-93 027 % Copyright (c) Anders Holtsberg 028 029 error(nargchk(3,3,nargin)) 030 [errorcode x,a,b] = comnsize(x,a,b); 031 if errorcode>0, 032 error('x, a and b must be of common size or scalar'); 033 end 034 035 F = zeros(size(x)); 036 037 ok = (a>0 & b>0); 038 039 Ii = find(x>0&x<1 & ok); 040 if any(Ii) 041 F(Ii) = betainc(x(Ii),a(Ii),b(Ii)); 042 end 043 044 Iu = find(x>=1); 045 if any(Iu) 046 F(Iu) = ones(size(Iu)); 047 end 048 049 k=find(~ok); 050 if (any(k)), 051 F(k)=NaN; 052 end 053 054 055 056 057 058
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