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Function Reference: logiinv

statistics: x = logiinv (p, mu, sigma)

Inverse of the logistic cumulative distribution function (iCDF).

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

Both parameters must be reals and sigma > 0. For sigma <= 0, NaN is returned.

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

See also: logicdf, logipdf, logirnd, logifit, logilike, logistat

Source Code: logiinv

Example: 1

 

 ## Plot various iCDFs from the logistic distribution
 p = 0.001:0.001:0.999;
 x1 = logiinv (p, 5, 2);
 x2 = logiinv (p, 9, 3);
 x3 = logiinv (p, 9, 4);
 x4 = logiinv (p, 6, 2);
 x5 = logiinv (p, 2, 1);
 plot (p, x1, "-b", p, x2, "-g", p, x3, "-r", p, x4, "-c", p, x5, "-m")
 grid on
 legend ({"μ = 5, σ = 2", "μ = 9, σ = 3", "μ = 9, σ = 4", ...
          "μ = 6, σ = 2", "μ = 2, σ = 1"}, "location", "southeast")
 title ("Logistic iCDF")
 xlabel ("probability")
 ylabel ("x")

                    
plotted figure