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Incomplete output Z88OS on Mac

Verfasst: Di 11. Aug 2015, 13:52
von MMathot
Dear all,

In my quest for automatically creating z88 input files from a parametric model in Grasshopper, I have stumbled upon a peculiar problem: the created input files (included in the attachment) do render a full, correct set of output after running z88r.exe on a windows machine, but do not render nodal forces in the z88o4.txt output after running on a mac 10.10.2 Yosemite machine. The z88o0 to z88o3 appear to be correct, including the displacements and rotations, but all values in the z88o4 file on the mac are just 0.0000...
I have been looking hard to find any inconsistency that might cause this problem, but just can't figure out what's wrong. Does anyone here have a clue?

Thanks in advance!

Re: Incomplete output Z88OS on Mac

Verfasst: Di 11. Aug 2015, 16:48
von SHautsch
Dear MMathot,

I just had a quick look at your project files and couldn't find an error. They run fine on Windows and Unix (Ubuntu 14.04 LTS) but under OS X the nodal forces are not calculated. Maybe there's an error :roll: - we will look into that as soon as possible.

In the meantime you could try to check the source code on your own and/or compile the solver for your operating system - maybe that helps. Otherwise please give us some time to check the solver and come back with to you with a solution.

Kind regards,
SHautsch

Re: Incomplete output Z88OS on Mac

Verfasst: Mi 12. Aug 2015, 12:52
von MMathot
Thank you for your quick response!

I will review as far as I can understand (not really an expert programmer ;), and report back if I do find a solution.

Re: Incomplete output Z88OS on Mac

Verfasst: Do 13. Aug 2015, 17:13
von SHautsch
Dear MMathot,

it seems that the problem results from the allocation of memory for the arrays in the z88r-source for unix. The memory is allocated statically (as it can be seen in z88v14os/src/z88r/unix/z88r.c line 223 ff.) which leads to a cache overflow produced by the compiler cache limits on OS X.
The only solution would be to change the memory allocation to a dynamic way.
We will sure keep that in mind for a new version of Z88OS, but for now you would have to do that on your own :|

Kind regards,
SHautsch