Accelerating MATLAB Performance

394 Accelerating MATLAB

®

Performance

8.1.3 MEX Function Inputs and Outputs

As noted above, the MEX gateway function mexFunction() is dened as follows:

void mexFunction (

int nlhs, /* number of expected outputs */

mxArray *plhs[], /* array of pointers to output args */

int nrhs, /* number of input args */

const mxArray *prhs[]) /* array of pointers to input args */

The format is simple: a pair of gateway inputs that denes the MEX function’s outputs

(number of requested arguments and a corresponding array of pointers to them), and

another pair that denes the MEX function’s inputs (number of specied arguments

and an array of pointers to them). MATLAB automatically sets mexFunction’s input args

(nlhs etc.) based on the actual inpu