Function Reference: ncx2cdf

statistics: p = ncx2cdf (x, df, delta)
statistics: p = ncx2cdf (x, df, delta, uflag)

Noncentral Chi-Square cumulative distribution function (CDF).

p = ncx2cdf (x, df, delta) returns the noncentral chi-square cdf with df degrees of freedom and noncentrality parameter delta at the values of x.

The size of p is the common size of the input arguments. Scalar input arguments x, df, delta are regarded as constant matrices of the same size as the other inputs.

p = ncx2cdf (x, df, delta, "upper" returns the upper tail probability of the noncentral chi-square distribution with df degrees of freedom and noncentrality parameter delta at the values in x.

See also: ncx2inv, ncx2pdf, ncx2rnd, ncx2stat

Source Code: ncx2cdf

Example: 1

 

 ## Compare the noncentral chi-square cdf with DELTA = 2 to the
 ## chi-square cdf with the same number of degrees of freedom (4):

 x = (0:0.1:10)';
 ncx2 = ncx2cdf (x, 4, 2);
 chi2 = chi2cdf (x, 4);
 plot(x, ncx2, "b-", "LineWidth", 2);
 hold on
 plot (x, chi2, "g--", "LineWidth", 2);
 legend ("ncx2", "chi2", "Location", "NorthWest");

                    
plotted figure