Enum polars::chunked_array::object::ArrowDataType

pub enum ArrowDataType {
    Null,
    Boolean,
    Int8,
    Int16,
    Int32,
    Int64,
    UInt8,
    UInt16,
    UInt32,
    UInt64,
    Float16,
    Float32,
    Float64,
    Timestamp(TimeUnit, Option<String>),
    Date32,
    Date64,
    Time32(TimeUnit),
    Time64(TimeUnit),
    Duration(TimeUnit),
    Interval(IntervalUnit),
    Binary,
    FixedSizeBinary(i32),
    LargeBinary,
    Utf8,
    LargeUtf8,
    List(Box<Field, Global>),
    FixedSizeList(Box<Field, Global>, i32),
    LargeList(Box<Field, Global>),
    Struct(Vec<Field, Global>),
    Union(Vec<Field, Global>, Option<Vec<i32, Global>>, bool),
    Dictionary(Box<DataType, Global>, Box<DataType, Global>),
    Decimal(usize, usize),
    Extension(String, Box<DataType, Global>, Option<String>),
}

The set of supported logical types. Each variant uniquely identifies a logical type, which define specific semantics to the data (e.g. how it should be represented). A DataType has an unique corresponding [PhysicalType], obtained via DataType::to_physical_type, which uniquely identifies an in-memory representation of data. The DataType::Extension is special in that it augments a DataType with metadata to support custom types. Use to_logical_type to desugar such type and return its correspoding logical type.

Variants

Null

Null type

Boolean

true and false.

Int8

A signed 8-bit integer.

Int16

A signed 16-bit integer.

Int32

A signed 32-bit integer.

Int64

A signed 64-bit integer.

UInt8

An unsigned 8-bit integer.

UInt16

An unsigned 16-bit integer.

UInt32

An unsigned 32-bit integer.

UInt64

An unsigned 64-bit integer.

Float16

A 16-bit floating point number.

Float32

A 32-bit floating point number.

Float64

A 64-bit floating point number.

Timestamp(TimeUnit, Option<String>)

A timestamp with an optional timezone.

Time is measured as a Unix epoch, counting the seconds from 00:00:00.000 on 1 January 1970, excluding leap seconds, as a 64-bit integer.

The time zone is a string indicating the name of a time zone, one of:

• As used in the Olson time zone database (the “tz database” or “tzdata”), such as “America/New_York”
• An absolute time zone offset of the form +XX:XX or -XX:XX, such as +07:30

Tuple Fields of Timestamp

0: TimeUnit1: Option<String>

Date32

A 32-bit date representing the elapsed time since UNIX epoch (1970-01-01) in days (32 bits).

Date64

A 64-bit date representing the elapsed time since UNIX epoch (1970-01-01) in milliseconds (64 bits). Values are evenly divisible by 86400000.

Time32(TimeUnit)

A 32-bit time representing the elapsed time since midnight in the unit of TimeUnit.

Tuple Fields of Time32

0: TimeUnit

Time64(TimeUnit)

A 64-bit time representing the elapsed time since midnight in the unit of TimeUnit.

Tuple Fields of Time64

0: TimeUnit

Duration(TimeUnit)

Measure of elapsed time in either seconds, milliseconds, microseconds or nanoseconds.

Tuple Fields of Duration

0: TimeUnit

Interval(IntervalUnit)

A “calendar” interval which models types that don’t necessarily have a precise duration without the context of a base timestamp (e.g. days can differ in length during day light savings time transitions).

Tuple Fields of Interval

0: IntervalUnit

Binary

Opaque binary data of variable length.

FixedSizeBinary(i32)

Opaque binary data of fixed size. Enum parameter specifies the number of bytes per value.

Tuple Fields of FixedSizeBinary

0: i32

LargeBinary

Opaque binary data of variable length and 64-bit offsets.

Utf8

A variable-length string in Unicode with UTF-8 encoding.

LargeUtf8

A variable-length string in Unicode with UFT-8 encoding and 64-bit offsets.

List(Box<Field, Global>)

A list of some logical data type with variable length.

Tuple Fields of List

0: Box<Field, Global>

FixedSizeList(Box<Field, Global>, i32)

A list of some logical data type with fixed length.

Tuple Fields of FixedSizeList

0: Box<Field, Global>1: i32

LargeList(Box<Field, Global>)

A list of some logical data type with variable length and 64-bit offsets.

Tuple Fields of LargeList

0: Box<Field, Global>

Struct(Vec<Field, Global>)

A nested datatype that contains a number of sub-fields.

Tuple Fields of Struct

0: Vec<Field, Global>

Union(Vec<Field, Global>, Option<Vec<i32, Global>>, bool)

A nested datatype that can represent slots of differing types. Third argument represents sparsness

Tuple Fields of Union

0: Vec<Field, Global>1: Option<Vec<i32, Global>>2: bool

Dictionary(Box<DataType, Global>, Box<DataType, Global>)

A dictionary encoded array (key_type, value_type), where each array element is an index of key_type into an associated dictionary of value_type.

Dictionary arrays are used to store columns of value_type that contain many repeated values using less memory, but with a higher CPU overhead for some operations.

This type mostly used to represent low cardinality string arrays or a limited set of primitive types as integers.

Tuple Fields of Dictionary

0: Box<DataType, Global>1: Box<DataType, Global>

Decimal(usize, usize)

Decimal value with precision and scale precision is the number of digits in the number and scale is the number of decimal places. The number 999.99 has a precision of 5 and scale of 2.

Tuple Fields of Decimal

0: usize1: usize

Extension(String, Box<DataType, Global>, Option<String>)

Extension type.

Tuple Fields of Extension

0: String1: Box<DataType, Global>2: Option<String>

Implementations

impl DataType

pub fn to_physical_type(&self) -> PhysicalType

the [PhysicalType] of this DataType.

pub fn to_logical_type(&self) -> &DataType

Returns &self for all but DataType::Extension. For DataType::Extension, (recursively) returns the inner DataType. Never returns the variant DataType::Extension.

Trait Implementations

impl Clone for DataType

pub fn clone(&self) -> DataType

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DataType

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Display for DataType

pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'_> From<&'_ DataType> for DataType

pub fn from(dt: &DataType) -> DataType

Performs the conversion.

impl Hash for DataType

pub fn hash<__H>(&self, state: &mut __H) where
    __H: Hasher, 

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl PartialEq<DataType> for DataType

pub fn eq(&self, other: &DataType) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PartialEq<DataType> for DataType

pub fn eq(&self, other: &DataType) -> bool

This method tests for self and other values to be equal, and is used by ==.

pub fn ne(&self, other: &DataType) -> bool

This method tests for !=.

impl Eq for DataType

impl StructuralEq for DataType

impl StructuralPartialEq for DataType