Hi Heinrich,
> the appended file test.mod is examples/threads/clustering.mod with
> appended line
>
> printf {t in T} "%d -> %d\n", t, pt[t];
>
> Essentially the line prints out part of the generated problem.
>
> The output on x86-64 ends with:
>
> 49 -> 608
> 50 -> 334
> Model has been successfully processed
>
> The output on ARMv7 ends with:
>
> 49 -> 852
> 50 -> 472
> Model has been successfully processed
>
> How can it be that the generated model differs depending on the CPU
> architecture?
I think this is due to round-off errors, because you are using
floating-point computations in your model.
Please conduct the following experiment: move the statement
printf {t in T} "%d -> %d\n", t, pt[t];
immediately before 'minimize', i.e. make it the very first one.
And then compare the output for both platforms.
BTW, does ARMv7 use the same floating-point representation (including
long double) as x86-64?
>
> If I run
> printf {1..10000} "%16.15f\n", Uniform01();
> I get the same result on both architectures:
>
> 0.443241402972490
> Model has been successfully generated
>
> So it is not a problem in the random number generation.
>
> If I remove all variables and constraints from appended test.mod I also
> get the same result on both architectures.
>
Best,
Andrew Makhorin
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