[ARROW-12677] [Python] Add a mask argument to pyarrow.StructArray.from_arrays

• Type: Improvement
• Status: Resolved
• Priority: Trivial
• Resolution: Fixed
• Fix Version/s: 5.0.0
• Component/s: Python
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/28425
• Assignee: Weston Pace
• Reporter: &res
• Created: 07/May/21 07:45
• Updated: 11/Jan/23 08:28
• Resolved: 14/May/21 20:48

Description

The python API for creating StructArray from a list of array doesn't allow to pass a missing value mask.

At the moment the only way to create a StructArray with missing value is to use `pyarrow.array` and passing a vector of tuple.

>>> pyarrow.array(
    [
        None,
        (1, "foo"),
    ],
    type=pyarrow.struct(
        [pyarrow.field('col1', pyarrow.int64()), pyarrow.field("col2", pyarrow.string())]
    )
)
-- is_valid:
  [
    false,
    true
  ]
-- child 0 type: int64
  [
    0,
    1
  ]
-- child 1 type: string
  [
    "",
    "foo"
  ]
>>> pyarrow.StructArray.from_arrays(
    [
        [None, 1],
        [None, "foo"]
    ],
    fields=[pyarrow.field('col1', pyarrow.int64()), pyarrow.field("col2", pyarrow.string())]
)
-- is_valid: all not null
-- child 0 type: int64
  [
    null,
    1
  ]
-- child 1 type: string
  [
    null,
    "foo"
  ]

The C++ API allows it, so it should be easy to add.

see this so question

Issue Links

• links to: GitHub Pull Request #10272