Man Scilab

dlgamma
Scilab Function

dlgamma - derivative of gammaln function, psi function

Calling Sequence

y = dlgamma(x)

Parameters

Description

dlgamma(x) evaluates, at all the elements of x the logarithmic derivative of the gamma function which corresponds also to the derivative of the gammaln function :


         d/dx (gamma(x)) / gamma(x) = d/dx (ln gamma(x))
     
    

x must be real. Also known as the psi function.

Examples


dlgamma(0.5)

 
  

See Also

gamma ,   gammaln ,  

Author

W. J. Cody (code from Netlib (specfun))

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