matlab script when run on simulink through matlab function block gives different outputs.

hi, I have written a matlab script for executing an iterative algorithm. I wish to make a simulink model out of it. Since, the algorithm was complicated enough , hence i thought to use matlab function block directly in simulink with appropriate inputs. Now, the same code when run in simulink is giving me different answer and the difference is substantial.

What am i missing here?

Inputs are much appreciated!

[Kaustubha Govind]

More information, like snippets from your code and how the outputs vary exactly will help us answer your question better.