not all grid attributes written

[ipelupessy]

Describe the bug
some grid attributes (of the "hidden" type) like _axes_names or the added derived attributes ("position") are not written with write_set_to_file, hence when reading some
method (e.g. get_axes_names) do not work

To Reproduce

g=new_cartesian_grid((5,5), 1)
write_set_to_file(g,"test.amuse","amuse")
g=read_set_from_file("test.amuse","amuse")
print(g.get_axes_names())

results in:

Exception: do not know how to find axes_names

Expected behavior
that it works

there are a few possible solutions, like _axes_names moving to collection_attributes, needs a bit of care

[stale]

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[ipelupessy]

this needs to be confirmed as fixed or not 100% fixed (think the latter)

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 28 days if no further activity occurs. Thank you for your contributions.

[Sbte]

I'm running into this as well. I also tried to fix it, but it seems difficult with how everything is set up, and without much knowledge of the underlying code.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 28 days if no further activity occurs. Thank you for your contributions.