Module polars_arrow::array

Contains the Array and MutableArray trait objects declaring arrays, as well as concrete arrays (such as Utf8Array and MutableUtf8Array).

Fixed-length containers with optional values that are laid in memory according to the Arrow specification. Each array type has its own struct. The following are the main array types:

• PrimitiveArray and MutablePrimitiveArray, an array of values with a fixed length such as integers, floats, etc.
• BooleanArray and MutableBooleanArray, an array of boolean values (stored as a bitmap)
• Utf8Array and MutableUtf8Array, an array of variable length utf8 values
• BinaryArray and MutableBinaryArray, an array of opaque variable length values
• ListArray and MutableListArray, an array of arrays (e.g. [[1, 2], None, [], [None]])
• StructArray and MutableStructArray, an array of arrays identified by a string (e.g. {"a": [1, 2], "b": [true, false]}) All immutable arrays implement the trait object Array and that can be downcasted to a concrete struct based on PhysicalType available from Array::data_type. All immutable arrays are backed by Buffer and thus cloning and slicing them is O(1).

Most arrays contain a MutableArray counterpart that is neither clonable nor sliceable, but can be operated in-place.

Modules

• growable
  Contains the trait Growable and corresponding concreate implementations, one per concrete array, that offer the ability to create a new Array out of slices of existing Arrays.
• physical_binary

Structs

• ArrayValuesIter
  Iterator of values of an [ArrayAccessor].
• BinaryArray
  A BinaryArray is Arrow’s semantically equivalent of an immutable Vec<Option<Vec<u8>>>. It implements Array.
• BooleanArray
  A BooleanArray is Arrow’s semantically equivalent of an immutable Vec<Option<bool>>. It implements Array.
• DictionaryArray
  An Array whose values are stored as indices. This Array is useful when the cardinality of values is low compared to the length of the Array.
• FixedSizeBinaryArray
  The Arrow’s equivalent to an immutable Vec<Option<[u8; size]>>. Cloning and slicing this struct is O(1).
• FixedSizeListArray
  The Arrow’s equivalent to an immutable Vec<Option<[T; size]>> where T is an Arrow type. Cloning and slicing this struct is O(1).
• ListArray
  An Array semantically equivalent to Vec<Option<Vec<Option<T>>>> with Arrow’s in-memory.
• MapArray
  An array representing a (key, value), both of arbitrary logical types.
• MutableBinaryArray
  The Arrow’s equivalent to Vec<Option<Vec<u8>>>. Converting a MutableBinaryArray into a BinaryArray is O(1).
• MutableBinaryValuesArray
  A MutableArray that builds a BinaryArray. It differs from MutableBinaryArray in that it builds non-null BinaryArray.
• MutableBooleanArray
  The Arrow’s equivalent to Vec<Option<bool>>, but with 1/16 of its size. Converting a MutableBooleanArray into a BooleanArray is O(1).
• MutableDictionaryArray
• MutableFixedSizeBinaryArray
  The Arrow’s equivalent to a mutable Vec<Option<[u8; size]>>. Converting a MutableFixedSizeBinaryArray into a FixedSizeBinaryArray is O(1).
• MutableFixedSizeListArray
  The mutable version of FixedSizeListArray.
• MutableListArray
  The mutable version of ListArray.
• MutableNullArray
  A distinct type to disambiguate clashing methods
• MutablePrimitiveArray
  The Arrow’s equivalent to Vec<Option<T>> where T is byte-size (e.g. i32). Converting a MutablePrimitiveArray into a PrimitiveArray is O(1).
• MutableStructArray
  Converting a MutableStructArray into a StructArray is O(1).
• MutableUtf8Array
  A MutableArray that builds a Utf8Array. It differs from MutableUtf8ValuesArray in that it can build nullable Utf8Arrays.
• MutableUtf8ValuesArray
  A MutableArray that builds a Utf8Array. It differs from MutableUtf8Array in that it builds non-null Utf8Array.
• NullArray
  The concrete Array of ArrowDataType::Null.
• PrimitiveArray
  A PrimitiveArray is Arrow’s semantically equivalent of an immutable Vec<Option<T>> where T is NativeType (e.g. i32). It implements Array.
• StructArray
  A StructArray is a nested Array with an optional validity representing multiple Array with the same number of rows.
• UnionArray
  UnionArray represents an array whose each slot can contain different values.
• Utf8Array
  A Utf8Array is arrow’s semantic equivalent of an immutable Vec<Option<String>>. Cloning and slicing this struct is O(1).

Traits

• Array
  A trait representing an immutable Arrow array. Arrow arrays are trait objects that are infallibly downcasted to concrete types according to the Array::data_type.
• Arrow2Arrow
  Trait providing bi-directional conversion between polars_arrow Array and arrow-rs ArrayData
• DictionaryKey
  Trait denoting NativeTypes that can be used as keys of a dictionary.
• GenericBinaryArray
  Trait that BinaryArray and Utf8Array implement for the purposes of DRY.
• MutableArray
  A trait describing a mutable array; i.e. an array whose values can be changed. Mutable arrays cannot be cloned but can be mutated in place, thereby making them useful to perform numeric operations without allocations. As in Array, concrete arrays (such as MutablePrimitiveArray) implement how they are mutated.
• PushUnchecked
  A trait describing the ability of a struct to receive new items.
• TryExtend
  A trait describing the ability of a struct to create itself from a iterator. This is similar to Extend, but accepted the creation to error.
• TryExtendFromSelf
  A trait describing the ability of a struct to extend from a reference of itself. Specialization of TryExtend.
• TryPush
  A trait describing the ability of a struct to receive new items.

Functions

• clone
  Clones a dynamic Array.
• equal
  Logically compares two Arrays. Two arrays are logically equal if and only if:
• from_data
  Convert an arrow_data::ArrayData to polars_arrow Array
• get_display
  Returns a function that writes the element of array at position index to a Write, writing null to the null slots.
• get_value_display
  Returns a function that writes the value of the element of array at position index to a Write, writing null in the null slots.
• new_empty_array
  Creates a new Array with a Array::len of 0.
• new_null_array
  Creates a new Array of ArrowDataType data_type and length. The array is guaranteed to have Array::null_count equal to Array::len for all types except Union, which does not have a validity.
• to_data
  Convert an polars_arrow Array to arrow_data::ArrayData

Type Aliases

• BinaryValueIter
  Iterator of values of an BinaryArray.
• DaysMsArray
  A type definition PrimitiveArray for days_ms
• DaysMsVec
  A type definition MutablePrimitiveArray for days_ms
• Float16Array
  A type definition PrimitiveArray for f16
• Float16Vec
  A type definition MutablePrimitiveArray for f16
• Float32Array
  A type definition PrimitiveArray for f32
• Float32Vec
  A type definition MutablePrimitiveArray for f32
• Float64Array
  A type definition PrimitiveArray for f64
• Float64Vec
  A type definition MutablePrimitiveArray for f64
• Int8Array
  A type definition PrimitiveArray for i8
• Int8Vec
  A type definition MutablePrimitiveArray for i8
• Int16Array
  A type definition PrimitiveArray for i16
• Int16Vec
  A type definition MutablePrimitiveArray for i16
• Int32Array
  A type definition PrimitiveArray for i32
• Int32Vec
  A type definition MutablePrimitiveArray for i32
• Int64Array
  A type definition PrimitiveArray for i64
• Int64Vec
  A type definition MutablePrimitiveArray for i64
• Int128Array
  A type definition PrimitiveArray for i128
• Int128Vec
  A type definition MutablePrimitiveArray for i128
• Int256Array
  A type definition PrimitiveArray for i256
• Int256Vec
  A type definition MutablePrimitiveArray for i256
• ListValuesIter
  Iterator of values of a ListArray.
• MonthsDaysNsArray
  A type definition PrimitiveArray for months_days_ns
• MonthsDaysNsVec
  A type definition MutablePrimitiveArray for months_days_ns
• UInt8Array
  A type definition PrimitiveArray for u8
• UInt8Vec
  A type definition MutablePrimitiveArray for u8
• UInt16Array
  A type definition PrimitiveArray for u16
• UInt16Vec
  A type definition MutablePrimitiveArray for u16
• UInt32Array
  A type definition PrimitiveArray for u32
• UInt32Vec
  A type definition MutablePrimitiveArray for u32
• UInt64Array
  A type definition PrimitiveArray for u64
• UInt64Vec
  A type definition MutablePrimitiveArray for u64
• Utf8ValuesIter
  Iterator of values of an Utf8Array.