Struct parquet::file::metadata::LevelHistogram

pub struct LevelHistogram { /* private fields */ }

Histograms for repetition and definition levels.

Each histogram is a vector of length max_level + 1. The value at index i is the number of values at level i.

For example, vec[0] is the number of rows with level 0, vec[1] is the number of rows with level 1, and so on.

Implementations

impl LevelHistogram

pub fn try_new(max_level: i16) -> Option<Self>

Creates a new level histogram data.

Length will be max_level + 1.

Returns None when max_level == 0 (because histograms are not necessary in this case)

pub fn values(&self) -> &[i64]

Returns a reference to the the histogram’s values.

pub fn into_inner(self) -> Vec<i64>

Return the inner vector, consuming self

pub fn get(&self, index: usize) -> Option<i64>

Returns the histogram value at the given index.

The value of i is the number of values with level i. For example, get(1) returns the number of values with level 1.

Returns None if the index is out of bounds.

pub fn add(&mut self, other: &Self)

Adds the values from the other histogram to this histogram

Panics

If the histograms have different lengths

pub fn len(&self) -> usize

return the length of the histogram

pub fn is_empty(&self) -> bool

returns if the histogram is empty

pub fn reset(&mut self)

Sets the values of all histogram levels to 0.

pub fn update_from_levels(&mut self, levels: &[i16])

Updates histogram values using provided repetition levels

Panics

if any of the levels is greater than the length of the histogram ( the argument supplied to Self::try_new)

Trait Implementations

impl Clone for LevelHistogram

fn clone(&self) -> LevelHistogram

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for LevelHistogram

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

Formats the value using the given formatter.

impl Default for LevelHistogram

fn default() -> LevelHistogram

Returns the “default value” for a type.

impl From<LevelHistogram> for Vec<i64>

fn from(value: LevelHistogram) -> Self

Converts to this type from the input type.

impl From<Vec<i64>> for LevelHistogram

fn from(inner: Vec<i64>) -> Self

Converts to this type from the input type.

impl Hash for LevelHistogram

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

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for LevelHistogram

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for LevelHistogram

impl StructuralPartialEq for LevelHistogram