Struct polars::prelude::StructArray

pub struct StructArray { /* private fields */ }

Available on crate feature polars-io only.

A StructArray is a nested [Array] with an optional validity representing multiple [Array] with the same number of rows.

Example

use polars_arrow::array::*;
use polars_arrow::datatypes::*;
let boolean = BooleanArray::from_slice(&[false, false, true, true]).boxed();
let int = Int32Array::from_slice(&[42, 28, 19, 31]).boxed();

let fields = vec![
    Field::new("b", ArrowDataType::Boolean, false),
    Field::new("c", ArrowDataType::Int32, false),
];

let array = StructArray::new(ArrowDataType::Struct(fields), vec![boolean, int], None);

Implementations

impl<'a> StructArray

pub fn iter( &'a self ) -> ZipValidity<Vec<Box<dyn Scalar>>, StructValueIter<'a>, BitmapIter<'a>>

Returns an iterator of Option<Box<dyn Array>>

pub fn values_iter(&'a self) -> StructValueIter<'a>

Returns an iterator of Box<dyn Array>

impl StructArray

pub fn try_new( data_type: ArrowDataType, values: Vec<Box<dyn Array>>, validity: Option<Bitmap> ) -> Result<StructArray, PolarsError>

Returns a new StructArray.

Errors

This function errors iff:

• data_type’s physical type is not [crate::datatypes::PhysicalType::Struct].
• the children of data_type are empty
• the values’s len is different from children’s length
• any of the values’s data type is different from its corresponding children’ data type
• any element of values has a different length than the first element
• the validity’s length is not equal to the length of the first element

pub fn new( data_type: ArrowDataType, values: Vec<Box<dyn Array>>, validity: Option<Bitmap> ) -> StructArray

Returns a new StructArray

Panics

This function panics iff:

• data_type’s physical type is not [crate::datatypes::PhysicalType::Struct].
• the children of data_type are empty
• the values’s len is different from children’s length
• any of the values’s data type is different from its corresponding children’ data type
• any element of values has a different length than the first element
• the validity’s length is not equal to the length of the first element

pub fn new_empty(data_type: ArrowDataType) -> StructArray

Creates an empty StructArray.

pub fn new_null(data_type: ArrowDataType, length: usize) -> StructArray

Creates a null StructArray of length length.

impl StructArray

pub fn into_data(self) -> (Vec<Field>, Vec<Box<dyn Array>>, Option<Bitmap>)

Deconstructs the StructArray into its individual components.

pub fn slice(&mut self, offset: usize, length: usize)

Slices this StructArray.

Panics

• offset + length must be smaller than self.len().

Implementation

This operation is O(F) where F is the number of fields.

pub unsafe fn slice_unchecked(&mut self, offset: usize, length: usize)

Slices this StructArray.

Implementation

This operation is O(F) where F is the number of fields.

Safety

The caller must ensure that offset + length <= self.len().

pub fn sliced(self, offset: usize, length: usize) -> StructArray

Returns this array sliced.

Implementation

This function is O(1).

Panics

iff offset + length > self.len().

pub unsafe fn sliced_unchecked( self, offset: usize, length: usize ) -> StructArray

Returns this array sliced.

Implementation

This function is O(1).

Safety

The caller must ensure that offset + length <= self.len().

pub fn with_validity(self, validity: Option<Bitmap>) -> StructArray

Returns this array with a new validity.

Panic

Panics iff validity.len() != self.len().

pub fn set_validity(&mut self, validity: Option<Bitmap>)

Sets the validity of this array.

Panics

This function panics iff values.len() != self.len().

pub fn take_validity(&mut self) -> Option<Bitmap>

Takes the validity of this array, leaving it without a validity mask.

pub fn boxed(self) -> Box<dyn Array>

Boxes this array into a Box<dyn Array>.

pub fn arced(self) -> Arc<dyn Array>

Arcs this array into a std::sync::Arc<dyn Array>.

impl StructArray

pub fn validity(&self) -> Option<&Bitmap>

The optional validity.

pub fn values(&self) -> &[Box<dyn Array>]

Returns the values of this StructArray.

pub fn fields(&self) -> &[Field]

Returns the fields of this StructArray.

impl StructArray

pub fn get_fields(data_type: &ArrowDataType) -> &[Field]

Returns the fields the DataType::Struct.

Trait Implementations

impl Array for StructArray

fn as_any(&self) -> &(dyn Any + 'static)

Converts itself to a reference of Any, which enables downcasting to concrete types.

fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)

Converts itself to a mutable reference of Any, which enables mutable downcasting to concrete types.

fn len(&self) -> usize

The length of the [Array]. Every array has a length corresponding to the number of elements (slots).

fn data_type(&self) -> &ArrowDataType

The ArrowDataType of the [Array]. In combination with [Array::as_any], this can be used to downcast trait objects (dyn Array) to concrete arrays.

fn slice(&mut self, offset: usize, length: usize)

Slices this [Array].

unsafe fn slice_unchecked(&mut self, offset: usize, length: usize)

Slices the [Array].

fn to_boxed(&self) -> Box<dyn Array>

Clone a &dyn Array to an owned Box<dyn Array>.

fn validity(&self) -> Option<&Bitmap>

The validity of the [Array]: every array has an optional [Bitmap] that, when available specifies whether the array slot is valid or not (null). When the validity is None, all slots are valid.

fn with_validity(&self, validity: Option<Bitmap>) -> Box<dyn Array>

Clones this [Array] with a new new assigned bitmap.

fn is_empty(&self) -> bool

whether the array is empty

fn null_count(&self) -> usize

The number of null slots on this [Array].

fn is_null(&self, i: usize) -> bool

Returns whether slot i is null.

unsafe fn is_null_unchecked(&self, i: usize) -> bool

Returns whether slot i is null.

fn is_valid(&self, i: usize) -> bool

Returns whether slot i is valid.

fn sliced(&self, offset: usize, length: usize) -> Box<dyn Array>

Returns a slice of this [Array].

unsafe fn sliced_unchecked( &self, offset: usize, length: usize ) -> Box<dyn Array>

Returns a slice of this [Array].

impl Clone for StructArray

fn clone(&self) -> StructArray

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for StructArray

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

Formats the value using the given formatter.

impl<'a> From<GrowableStruct<'a>> for StructArray

fn from(val: GrowableStruct<'a>) -> StructArray

Converts to this type from the input type.

impl From<MutableStructArray> for StructArray

fn from(other: MutableStructArray) -> StructArray

Converts to this type from the input type.

impl<'a> IntoIterator for &'a StructArray

type Item = Option<Vec<Box<dyn Scalar>>>

The type of the elements being iterated over.

type IntoIter = ZipValidity<Vec<Box<dyn Scalar>>, StructValueIter<'a>, BitmapIter<'a>>

Which kind of iterator are we turning this into?

fn into_iter(self) -> <&'a StructArray as IntoIterator>::IntoIter

Creates an iterator from a value.

impl PartialEq<&(dyn Array + 'static)> for StructArray

fn eq(&self, other: &&(dyn Array + 'static)) -> 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 !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialEq for StructArray

fn eq(&self, other: &StructArray) -> 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 !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl TryFrom<StructArray> for DataFrame

type Error = PolarsError

The type returned in the event of a conversion error.

fn try_from(arr: StructArray) -> Result<DataFrame, PolarsError>

Performs the conversion.