Computes the Exponential quantile.
x = nisp_expinv ( p ) x = nisp_expinv ( p , lambda )
a matrix of doubles, the probability
a matrix of doubles
a matrix of doubles
This function computes the Exponential Quantile.
Any scalar input argument is expanded to a matrix of doubles of the same size as the other input arguments.
Any optional input argument equal to the empty matrix will be set to its default value.
This function might be inaccurate when p is close to 1.
TODO : improve implementation (check inf, nan, etc...)
// Check the inversion lambda=2; x=3; p = nisp_expcdf ( x , lambda ); // p = 0.9975212 x = nisp_expinv ( p , lambda ) // must be 3
Wikipedia, Exponential distribution function, http://en.wikipedia.org/wiki/Exponential_distribution