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Function Reference: wblinv

statistics: x = wblinv (p)
statistics: x = wblinv (p, lambda)
statistics: x = wblinv (p, lambda, k)

Inverse of the Weibull cumulative distribution function (iCDF).

For each element of p, compute the quantile (the inverse of the CDF) of the Weibull distribution with scale parameter lambda and shape parameter k. The size of x is the common size of p, lambda, and k. A scalar input functions as a constant matrix of the same size as the other inputs.

Default values are lambda = 1, k = 1.

Further information about the Weibull distribution can be found at https://en.wikipedia.org/wiki/Weibull_distribution

Input arguments must be double or single; integer, logical, and character arrays are rejected. MATLAB accepts a character array and evaluates it at the character codes, which Octave deliberately does not, since a character array is an integer type and integers are refused too.

The prob.WeibullDistribution class names these same two parameters A and B, after MATLAB. lambda is its A and k is its B.

See also: wblcdf, wblpdf, wblrnd, wblstat, wblplot

Source Code: wblinv

Plot various iCDFs from the Weibull distribution

 p = 0.001:0.001:0.999;
 x1 = wblinv (p, 1, 0.5);
 x2 = wblinv (p, 1, 1);
 x3 = wblinv (p, 1, 1.5);
 x4 = wblinv (p, 1, 5);
 plot (p, x1, '-b', p, x2, '-r', p, x3, '-m', p, x4, '-g')
 ylim ([0, 2.5])
 grid on
 legend ({'λ = 1, k = 0.5', 'λ = 1, k = 1',  ...
          'λ = 1, k = 1.5', 'λ = 1, k = 5'}, 'location', 'northwest')
 title ('Weibull iCDF')
 xlabel ('probability')
 ylabel ('x')
plotted figure