C-MEX file example for 'float' data types

Calling a C file from MATLAB, the C function (a high pass filter) has four arguments ...

Description

If you have a C function with arguments that are float or pointer to float (rather than double or pointer to double) you can call the function from MATLAB and pass arguments to the function as single data types. For example, in this case we have a C file that is a highpass filter. In MATLAB ver. 7 we pass arguments to the function as:

[out,mem]=hpinput(single(n),single(mem));

Note that mem is used both as input to the function and output to the function.

If the arguments to the C function were of type double or poiter to double, there was no need to use 'signle' type casting when we were calling the function in MATLAB.

To use this function in MATLAB you need to create a dll file by typing the following command in MATLAB:

mex hpinput.c

The C function is part of the publicly available code for the ILBC coder.

• MATLAB release: MATLAB 7.0.1 (R14SP1)

[Alex Su]