max.c
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	/*
	*
	* Copyright (C) 2007, Robert Oostenveld
	*
	* This implements [y, i] = max(x)
	*
	* This function does not check the occurence of integer overflowing.
	*
	*/

	#include <math.h>
	#include "mex.h"
	#include "matrix.h"

	void
	mexFunction (int nlhs, mxArray * plhs[], int nrhs, const mxArray * prhs[])
	{
	size_t M, N, n;
	UINT64_T x, m;
	double *i;

	if (nlhs > 2)
	mexErrMsgTxt ("Invalid number of output arguments");
	if (nrhs > 1)
	mexErrMsgTxt ("Invalid number of input arguments");

	if (!mxIsUint64(prhs[0]))
	mexErrMsgTxt ("Invalid type of input arguments (should be uint64)");

	M = mxGetM(prhs[0]);
	N = mxGetN(prhs[0]);

	if (N>1 & M>1)
	mexErrMsgTxt ("This works only on 1-D arrays (i.e. vectors)");

	if (N==0 & M==0)
	mexErrMsgTxt ("This works only on 1-D arrays (i.e. vectors)");


	plhs[0] = (mxArray*)mxCreateNumericMatrix(1, 1, mxUINT64_CLASS, mxREAL);
	plhs[1] = (mxArray*)mxCreateDoubleMatrix(1, 1, mxREAL);
	x = mxGetData(prhs[0]);
	m = mxGetData(plhs[0]);
	i = mxGetData(plhs[1]);

	n = 0;
	m[0] = x[n];
	i[0] = n+1; /* offset by one */

	for (n=1; n<(M*N); n++)
	if (x[n]>m[0])
	{
	m[0] = x[n];
	i[0] = n+1; /* offset by one */
	}

	return;
	}