Named axes in nested awkward arrays

[kumarneelabh13]

Description of new feature

Axis names are lost when an awkward array with named axes is nested inside another awkward array. (Example attached)

Can awkward array preserve the named axes?

[pfackeldey]

Hi @kumarneelabh13,

in order to preserve attrs (the metadata container that keeps track of named axis) you can use ak.zip instead:

awkward_array = ak.zip({
  "foo": ak.with_named_axis(ak.Array([1]), ("time",)),
  "bar": ak.Array([2]),
})
awkward_array.show(named_axis=True)
# axes: time:0
# [{foo: 1, bar: 2}]

This one will also make sure that you don't have named axis clashes:

awkward_array = ak.zip({
  "foo": ak.with_named_axis(ak.Array([1]), ("time",)),
  "bar": ak.with_named_axis(ak.Array([2]), ("space",))
})
# > ValueError: The named axes are incompatible. Got: time and space for positional axis 0

I'd say that for constructing record arrays it is usually preferred to use ak.zip instead of the ak.Array constructor. Can you confirm this @jpivarski ?