TYPECAST and TYPECASTX are mex functions intended to mimic the MATLAB intrinsic typecast function with extensions. These C-mex versions of typecast differs from the intrinsic typecast in the following important aspects:
Type of copy: Deep Data Copy
Allows complex: No
Allows logical: No
Allows char: No
Allows non-vector: No
Type of copy: Shared Data Copy
Allows complex: Yes
Allows logical: Yes (cannot convert from complex)
Allows char: Yes (cannot convert from complex)
Allows non-vector: Yes
Since these C-mex functions produce a shared data copy of the original, it is more efficient than the MATLAB intrinsic typecast, which may be important if you are working with large variables. For non-vector inputs, the first non-singleton dimension must be compatible for the conversion.
There is *NO* difference in functionality between the C-mex typecast and typecastx functions. The purpose of including typecastx is so that users can have the extended functionality shown above without shadowing the intrinsic typecast. e.g., users with older versions of MATLAB that do not have a MATLAB intrinsic typecast might install both typecast and typecastx, whereas users with later versions of MATLAB that *do* have an intrinsic typecast might choose to only install the typecastx function.
Note that these C-mex functions are self-building ... you don't have to know anything about C.