You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: glmgrad.m
    path of file: ./repos/pcm/matlab/lib/netlab3_3
    
    the code of the file until where you have to start completion: function [g, gdata, gprior] = glmgrad(net, x, t)
%GLMGRAD Evaluate gradient of error function for generalized linear model.
%
%	Description

    
function [g, gdata, gprior] = glmgrad(net, x, t)
%GLMGRAD Evaluate gradient of error function for generalized linear model.
%
%	Description
%	G = GLMGRAD(NET, X, T) takes a generalized linear model data
%	structure NET  together with a matrix X of input vectors and a matrix
%	T of target vectors, and evaluates the gradient G of the error
%	function with respect to the network weights. The error function
%	corresponds to the choice of output unit activation function. Each
%	row of X corresponds to one input vector and each row of T
%	corresponds to one target vector.
%
%	[G, GDATA, GPRIOR] = GLMGRAD(NET, X, T) also returns separately  the
%	data and prior contributions to the gradient.
%
%	See also
%	GLM, GLMPAK, GLMUNPAK, GLMFWD, GLMERR, GLMTRAIN
%

%	Copyright (c) Ian T Nabney (1996-2001)

% Check arguments for consistency
errstring = consist(net, 'glm', x, t);
if ~isempty(errstring);
  error(errstring);
end