User`s manual

Examples of C MEX-Files
2-7
Examples of C MEX-Files
The following sections include information and examples describing how to
pass and manipulate the different data types when working with MEX-files.
These topics include
•“A First Example — Passing a Scalar”
•“Passing Strings”
•“Passing Two or More Inputs or Outputs”
•“Passing Structures and Cell Arrays”
•“Handling Complex Data”
•“Handling 8-,16-, and 32-Bit Data”
•“Manipulating Multidimensional Numerical Arrays”
•“Handling Sparse Arrays”
•“Calling Functions from C MEX-Files”
The MATLAB API provides a full set of routines that handle the various data
types supported by MATLAB. For each data type there is a specific set of
functions that you can use for data manipulation. The first example discusses
the simple case of doubling a scalar. After that, the examples discuss how to
pass in, manipulate, and pass back various data types, and how to handle
multiple inputs and outputs. Finally, the sections discuss passing and
manipulating various MATLAB data types.
Note You can find the most recent versions of the example programs at the
anonymous FTP server
ftp://ftp.mathworks.com/pub/tech-support/docexamples/apiguide/R12/refbook
A First Example — Passing a Scalar
Let’s look at a simple example of C code and its MEX-file equivalent. Here is a
C computational function that takes a scalar and doubles it.
#include <math.h>
void timestwo(double y[], double x[])