Set units in QTable for multiple columns

[LibrEars]

Description

I would like to set the unit for multiple columns of a QTable

Expected behavior

Set the unit of multiple columns in one command:

table = QTable(names=["a","b","c","d","e"])

table["a"].unit = u.A        # works like expected
table["b", "c", "d"].unit = u.mV # does not work like expected

table[table.columns[1:3]].unit = u.mV # slicing would be nice but does not work eather

Actual behavior

table["b","c","d"] returns a copy of the table and not a view. Therefor the changing the units has no effect.

Workaround if someone stumbles about this:

Use a loop to set the unit for each column individually

for col in table.columns[1:3]:
    table[col].unit = u.mV  

Suggestion

If returning a view is not desirable, maybe an attribute table.units could be introduced, exposing some way to manipulate multiple units

table.units[1:3] = u.mV

# or maybe
table.units[table.columns[1:3]] = u.mV

System Details

Linux-5.10.0-12-amd64...
Python 3.9.2
Numpy 1.22.1
pyerfa 2.0.0.1
astropy 5.0.1
Scipy 1.7.3
Matplotlib 3.5.1

[github-actions]

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[neutrinoceros]

@taldcroft it looks to me that nothing is actually broken here and there's even a mention of a supported way of achieving the desired result so I would recommend changing the "bug" label for a "question" and close the issue as "won't fix".