pyarrow.ListScalar#

classpyarrow.ListScalar#

Bases:Scalar,Sequence

Concrete class for list-like scalars.

__init__(*args,**kwargs)#

Methods

__init__(*args, **kwargs)
as_py(self, *[, maps_as_pydicts])	Return this value as a Python list.
cast(self[, target_type, safe, options, ...])	Cast scalar value to another data type.
count(value)
equals(self, Scalar other)
index(value, [start, [stop]])	Raises ValueError if the value is not present.
validate(self, *[, full])	Perform validation checks.

Attributes

is_valid	Holds a valid (non-null) value.
type	Data type of the Scalar object.
values

as_py(self,*,maps_as_pydicts=None)#

Return this value as a Python list.

Parameters:

maps_as_pydictsstr, optional, defaultNone

Valid values areNone, ‘lossy’, or ‘strict’.The default behavior (None), is to convert Arrow Map arrays toPython association lists (list-of-tuples) in the same order as theArrow Map, as in [(key1, value1), (key2, value2), …].

If ‘lossy’ or ‘strict’, convert Arrow Map arrays to native Python dicts.

If ‘lossy’, whenever duplicate keys are detected, a warning will be printed.The last seen value of a duplicate key will be in the Python dictionary.If ‘strict’, this instead results in an exception being raised when detected.

cast(self,target_type=None,safe=None,options=None,memory_pool=None)#

Cast scalar value to another data type.

Seepyarrow.compute.cast() for usage.

Parameters:

target_typeDataType, defaultNone

Type to cast scalar to.

safebool, defaultTrue

Whether to check for conversion errors such as overflow.

optionsCastOptions, defaultNone

Additional checks pass by CastOptions

memory_poolMemoryPool, optional

memory pool to use for allocations during function execution.

Returns:

scalarAScalar ofthegiventargetdata type.

count(value)→integer--returnnumberofoccurrencesofvalue#

equals(self,Scalarother)#

Parameters:

otherpyarrow.Scalar

Returns:

bool

index(value[,start[,stop]])→integer--returnfirstindexofvalue.#

Raises ValueError if the value is not present.

Supporting start and stop arguments is optional, butrecommended.

is_valid#

Holds a valid (non-null) value.

type#

Data type of the Scalar object.

validate(self,*,full=False)#

Perform validation checks. An exception is raised if validation fails.

By default only cheap validation checks are run. Passfull=Truefor thorough validation checks (potentially O(n)).

Parameters:

fullbool, defaultFalse

If True, run expensive checks, otherwise cheap checks only.

Raises:

ArrowInvalid

values#