Raspberry Pi 2 cannot display a 7 segment display. Help Needed!!

I have recently programmed the Raspberry Pi 2 Model B with the python program from github for displaying on an Adafruit 0.56" Led display, and it displayed seamlessly. I tried to do the same with MATLAB, the displays didn't even turn on once. The i2c connection is detected. I followed every step as given in 7 segment display. But it diddn't work. Connection with Raspberry PI is fine. the GPIOs work with MATLAB and Simulink. It is weird and i cannot figure out why.

write(segmentDisp, 7); write(segmentDisp, hex2dec('a')); write(segmentDisp, hex2dec('b'));

i tried to write this and it displayed nothing. there is no error also in the Command window. Cannot even debug because i m clueless of the fault.

Thanks