Difference between MATLAB on Mac & Windows?

I running the exact same test on the exact same code (ensured by checking out the same revision of a code repository) on a Windows computer and on a Mac, and the test failed on Windows but passed on Mac.

I think I've controlled for all the differences between the two environments: in both scenarios Matlab is 8.4.0.150421 (R2014b), the relevant toolboxes all seem to be the same version, the path is set the same, and the code is exactly the same.

I did notice that the JVMs are different (Java 1.7.0_55-b13 on the Mac and Java 1.7.0_11-b21 on Windows), but it seems that the JVMs are packaged with Matlab, so I can't control that?

Any advice would be greatly appreciated.

[Walter Roberson]

What kind of test is failing?

[Tim]

It's a numerical computation that produces a vector as output. The output vector is compared to a ground truth vector (initially produced on the Mac), which passes on the Mac but fails on Windows despite having the exact same configuration (as far as I can tell).

[Sanjana Chhabra]

on copying and pasting code windows matlab automatically preserves the line break but macOS pastes all the code in one line. Can someone help??

[Walter Roberson]

What are you copying and pasting the code from, and to ?

Answer 1

[Walter Roberson]

The implementations on different operating systems are permitted to have different default rounding modes. Have a look at http://undocumentedmatlab.com/blog/undocumented-feature-function for information on feature() and system_dependent()

The different operating systems definitely have BLAS and LAPACK compiled differently, and on MS Windows you may being using Intel's MLK. MS Windows in particular is known for having a different version of MLK for different CPU architectures (AMD vs Intel for example, but even different families within a manufacturer.)

For this reason, you should not expect that the bottommost bits of a calculation will be exactly the same on different systems.

Answer 2

[jesus osiel moya fuentes]

What are the restrictions if I make an executable program on MAC or WINDOWS?

[Walter Roberson]

@jesus osiel moya fuentes

Mac does not support activex or .NET, or use of MATLAB as an Automation Engine

Mac does not support writing .xls or .xlsx files using xlswrite() -- but does support writing them with writetable(), writematrix(), and writecell()

There are some toolboxes that are not supported on Mac

There are probably some other items.