gamlike
              Negative log-likelihood for the Gamma distribution.
 nlogL = gamlike (params, x) returns the negative
 log likelihood of the data in x corresponding to the Gamma distribution
 with (1) shape parameter a and (2) scale parameter b given in the
 two-element vector params.
 [nlogL, acov] = gamlike (params, x) also
 returns the inverse of Fisher’s information matrix, acov.  If the input
 parameter values in params are the maximum likelihood estimates, the
 diagonal elements of acov are their asymptotic variances.
 […] = gamlike (params, x, censor) accepts a
 boolean vector, censor, of the same size as x with 1s for
 observations that are right-censored and 0s for observations that are
 observed exactly.  By default, or if left empty,
 censor = zeros (size (x)).
 […] = gamlike (params, x, censor, freq)
 accepts a frequency vector, freq, of the same size as x.
 freq typically contains integer frequencies for the corresponding
 elements in x, but it can contain any non-integer non-negative values.
 By default, or if left empty, freq = ones (size (x)).
OCTAVE/MATLAB use the alternative parameterization given by the pair , i.e. shape a and scale b. In Wikipedia, the two common parameterizations use the pairs , as shape and scale, and , as shape and rate, respectively. The parameter names a and b used here (for MATLAB compatibility) correspond to the parameter notation instead of the as reported in Wikipedia.
Further information about the Gamma distribution can be found at https://en.wikipedia.org/wiki/Gamma_distribution
See also: gamcdf, gampdf, gaminv, gamrnd, gamfit
Source Code: gamlike