Enum polars::datatypes::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>),
    Dictionary(Box<DataType, Global>, Box<DataType, Global>),
    Decimal(usize, usize),
}

The set of datatypes that are supported by this implementation of Apache Arrow.

The Arrow specification on data types includes some more types. See also Schema.fbs for Arrow’s specification.

The variants of this enum include primitive fixed size types as well as parametric or nested types. Currently the Rust implementation supports the following nested types:

• List<T>
• Struct<T, U, V, ...>

Nested types can themselves be nested within other arrays. For more information on these types please see the physical memory layout of Apache Arrow.

Variants

Null

Null type

Boolean

A boolean datatype representing the values 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

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.

Time64(TimeUnit)

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

Duration(TimeUnit)

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

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).

Binary

Opaque binary data of variable length.

FixedSizeBinary(i32)

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

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.

FixedSizeList(Box<Field, Global>, i32)

A list of some logical data type with fixed length.

LargeList(Box<Field, Global>)

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

Struct(Vec<Field, Global>)

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

Union(Vec<Field, Global>)

A nested datatype that can represent slots of differing types.

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.

Decimal(usize, usize)

Decimal value with precision and scale

Implementations

impl DataType

pub fn to_json(&self) -> Value

Generate a JSON representation of the data type.

pub fn is_numeric(t: &DataType) -> bool

Returns true if this type is numeric: (UInt*, Unit*, or Float*).

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<'de> Deserialize<'de> for DataType

pub fn deserialize<__D>(
    __deserializer: __D
) -> Result<DataType, <__D as Deserializer<'de>>::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

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 Ord for DataType

pub fn cmp(&self, other: &DataType) -> Ordering

This method returns an Ordering between self and other.

#[must_use]

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

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 ==.

#[must_use]

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 PartialOrd<DataType> for DataType

pub fn partial_cmp(&self, other: &DataType) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]

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

This method tests less than (for self and other) and is used by the < operator.

#[must_use]

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]

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

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for DataType

pub fn serialize<__S>(
    &self,
    __serializer: __S
) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.

impl Eq for DataType

impl StructuralEq for DataType

impl StructuralPartialEq for DataType