pyarrow.map_ — Apache Arrow v20.0.0 (original) (raw)

pyarrow.map_(key_type, item_type, keys_sorted=False) → MapType#

Create MapType instance from key and item data types or fields.

Parameters:

key_typeDataType or Field

item_typeDataType or Field

keys_sortedbool

Returns:

map_typeDataType

Examples

Create an instance of MapType:

import pyarrow as pa pa.map_(pa.string(), pa.int32()) MapType(map<string, int32>) pa.map_(pa.string(), pa.int32(), keys_sorted=True) MapType(map<string, int32, keys_sorted>)

Use MapType to create an array:

data = [[{'key': 'a', 'value': 1}, {'key': 'b', 'value': 2}], [{'key': 'c', 'value': 3}]] pa.array(data, type=pa.map_(pa.string(), pa.int32(), keys_sorted=True)) <pyarrow.lib.MapArray object at ...> [ keys: [ "a", "b" ] values: [ 1, 2 ], keys: [ "c" ] values: [ 3 ] ]