timestwo.cpp

来自「斯坦福Energy211/CME211课《c++编程——地球科学科学家和工程师》」· C++ 代码 · 共 29 行

#include "mex.h"

void timestwo_alt( double *y, double x )
{
	*y = 2.0 * x;
}

void mexFunction( int nlhs, mxArray *plhs[],
                  int nrhs, const mxArray *prhs[] )
{
	// Create a 1-by-1 matrix for the return argument
	plhs[0] = mxCreateDoubleMatrix( 1, 1, mxREAL );

	// Get the scalar value of the input x
	// Note: mxGetScalar returns a value, not a pointer
	double x = mxGetScalar( prhs[0] );

	// Assign a pointer to the output
	double *y = mxGetPr( plhs[0] );
  
	// Call the timestwo_alt subroutine to do the real
	// work.  Because y is pointing to the location
	// where MATLAB is storing the output value, we
	// only need to store the result at y for it to
	// be passed back to MATLAB automatically
	timestwo_alt(y, x);
}