How to remove a file extension?

Hello, I wanted to ask about how I can remove a file extension because I have a function to call without the extension :

For example:

function[] = main (input)

Where input is an XML file , and after a process that file need to call in another function within it without the XML extension.

That would read:

function = first ( ' file.xml ');

and later that file without the extension in another function within the .m file as :

function[] = second ( 'file ' ) ,

here already without the .xml extension. Thanks in advanced!

[Stephen23]

Please stop duplicating your question everywhere:

http://www.mathworks.com/matlabcentral/answers/284557-how-to-call-a-file-without-extension

You already asked this in a comment, and got a very thorough answer.