32 bit vs 64 bit machine effect in computing equal code

32bit and 64bit Windows don't compute the same result for the same code written and run with Matlab 32bit. The difference I have noted are few in a large calculus, but they are present. Shortly, my computation has not been exactly replicate with both machine. Why? How to control this machine effect?

[Stephen23]

This might be interesting as well:

https://www.mathworks.com/matlabcentral/answers/292072-does-the-matlab-version-affect-on-your-code-s-output

Answer 1

[Fei Deng]

Hi Alberto,

Some higher-level algorithms boiling down to basic arithmetic operations can result in different results, when they are performed in different environments due to the very nature of floating-point arithmetic.

I'd like to link this question to similar questions and answers here

http://www.mathworks.com/matlabcentral/answers/1032-why-do-some-calculations-like-the-fft-produce-different-results-when-performed-on-a-gpu

and here

https://www.mathworks.com/matlabcentral/answers/438-why-are-computational-results-in-matlab-sometimes-different-on-different-machines-and-how-can-i-prev