How to find mel frequency cepstral coefficients for a sound/audio file using direct command by adding which libraries and tool box. please explain in detail

I trying to find MFCC for an audio file by using command 'melcepst' but I am getting an error as undefined function.Is their any libraries or toolbox like voicebox toolbox to be added or installed.so that i can use the command.please suggest how to find MFCC and procedure for how to install the toolbox and make use of it if required.