pyarrow.map_#

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

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

Parameters:
key_typeDataType orField
item_typeDataType orField
keys_sortedbool
Returns:
map_typeDataType

Examples

Create an instance of MapType:

>>>importpyarrowaspa>>>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  ]]