Struct RunEndArray

pub struct RunEndArray { /* private fields */ }

Implementations

impl RunEndArray

pub fn new(ends: ArrayRef, values: ArrayRef) -> Self

Build a new RunEndArray from an array of run ends and an array of values.

Panics if any of the validation conditions described in RunEndArray::try_new is not satisfied.

Examples

let ends = buffer![2u8, 3u8].into_array();
let values = BoolArray::from_iter([false, true]).into_array();
let run_end = RunEndArray::new(ends, values);

// Array encodes
assert_eq!(run_end.scalar_at(0), false.into());
assert_eq!(run_end.scalar_at(1), false.into());
assert_eq!(run_end.scalar_at(2), true.into());

pub fn try_new(ends: ArrayRef, values: ArrayRef) -> VortexResult<Self>

Build a new RunEndArray from components.

Validation

The ends must be non-nullable unsigned integers. The values may be Bool or Primitive types.

All ends must be strictly monotonic. A run cannot be empty, therefore there can be no duplicates in the ends.

Examples

// Error to provide duplicate ends!
let result = RunEndArray::try_new(
    buffer![1u8, 1u8, 2u8].into_array(),
    buffer![100i32, 200i32, 300i32].into_array(),
);
assert!(result.is_err());

// Error to provide incorrectly-typed values!
let result = RunEndArray::try_new(
    buffer![1u8, 2u8].into_array(),
    VarBinViewArray::from_iter_str(["bad", "dtype"]).into_array(),
);
assert!(result.is_err());

// This array is happy
let result = RunEndArray::try_new(
    buffer![1u8, 2u8].into_array(),
    BoolArray::from_iter([false, true]).into_array(),
);

assert!(result.is_ok());

pub fn try_new_offset_length( ends: ArrayRef, values: ArrayRef, offset: usize, length: usize, ) -> VortexResult<Self>

Construct a new sliced RunEndArray with the provided offset and length.

This performs all the same validation as RunEndArray::try_new.

pub unsafe fn new_unchecked( ends: ArrayRef, values: ArrayRef, offset: usize, length: usize, ) -> Self

Build a new RunEndArray without validation.

Safety

The caller must ensure that all the validation performed in RunEndArray::try_new is satisfied before calling this function.

See RunEndArray::try_new for the preconditions needed to build a new array.

pub fn find_physical_index(&self, index: usize) -> usize

Convert the given logical index to an index into the values array

pub fn encode(array: ArrayRef) -> VortexResult<Self>

Run the array through run-end encoding.

pub fn offset(&self) -> usize

The offset that the ends is relative to.

This is generally zero for a “new” array, and non-zero after a slicing operation.

pub fn ends(&self) -> &ArrayRef

The encoded “ends” of value runs.

The i-th element indicates that there is a run of the same value, beginning at ends[i] (inclusive) and terminating at ends[i+1] (exclusive).

pub fn values(&self) -> &ArrayRef

The scalar values.

The i-th element is the scalar value for the i-th repeated run. The run begins at ends[i] (inclusive) and terminates at ends[i+1] (exclusive).

Trait Implementations

impl AsRef<dyn Array> for RunEndArray

fn as_ref(&self) -> &dyn Array

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for RunEndArray

fn clone(&self) -> RunEndArray

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RunEndArray

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

Formats the value using the given formatter.

impl Deref for RunEndArray

type Target = dyn Array

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl From<RunEndArray> for ArrayRef

fn from(value: RunEndArray) -> ArrayRef

Converts to this type from the input type.

impl IntoArray for RunEndArray

fn into_array(self) -> ArrayRef