strncmpr

Compare last N chars of strings or cell strings (fast C-Mex)

Compare last N chars of strings or cell strings

== FOR OLD MATLAB VERSIONS ONLY!

== Use EndsWith() in modern versions!

Input and output equal Matlab's STRNCMP/STRNCMPI, but the strings are compared from right to left.

T = strncmpr(S1, S2, N) or T = strncmpir(S1, S2, N)

INPUT:

S1, S2: Strings or cell strings.

N: Number of characters to compare.

OUTPUT:

T: Logical array, TRUE if the last N characters are equal, FALSE otherwise.

For STRNCMPIR the case is ignored.

Comparing just two strings in the backward direction can be done in Matlab with a fair efficiency. But for cell strings, this C-Mex is much faster than equivalent Matlab methods: e.g. 3% processing time for comparing a string with a {1 x 100} cell, 1% for {1 x 1000}. I apply it to identify the extensions of file names stored in cell strings.

Call the unit-test function Teststrncmpr to check validity and speed.

Tested: Matlab 6.5, 7.7, 7.8, WinXP, compatibility to Linux and OS-X assumed.

Compiler: LCC2.4/3.8, BCC5.5, OpenWatcom 1.8, MSVC 2008.

It is assumed that wchar_t has the same size as mxChar.

Pre-compiled Mex: http://www.n-simon.de/mex

I'd appreciate suggestions for improvements and bug reports sent through email - thanks.