Struct Index 

pub struct Index {
    pub name: Option<String>,
    pub kind: IndexKind,
}

Row labels plus an optional name.

name is index-wide metadata (pandas Index.name): it is recorded by set_index (from the source column), restored by reset_index, and shown in a frame’s / series’ repr. It is None for an unnamed index (the default Range index, a freshly built datetime index, …).

kind is the label storage. A Datetime kind carries its own Tz: storage is always UTC epoch-ns, but the tz governs how those instants render and how bare-string / day-bucket matching maps to wall-clock time (see crate::tz). Both the name and a datetime kind’s tz ride with the shared Arc<Index>, so a frame and every series drawn from it agree on them for free.

Fields

name: Option<String>

Optional index name (pandas Index.name); None when unnamed.

kind: IndexKind

The label storage / kind.

Implementations

impl Index

pub fn range(n: usize) -> Index

An unnamed implicit 0..n range index.

pub fn int64(labels: Vec<i64>) -> Index

An unnamed explicit integer index.

pub fn datetime(labels: Vec<i64>, tz: Tz) -> Index

An unnamed datetime index (UTC-ns labels, tagged with tz).

pub fn str(labels: Vec<String>) -> Index

An unnamed string index.

pub fn kind(&self) -> &IndexKind

The label storage / kind.

pub fn name(&self) -> Option<&str>

The index name, if any (pandas Index.name).

pub fn with_name(self, name: Option<String>) -> Index

Return this index with its name set (builder; consumes self).

pub fn from_column(col: &Column) -> Result<Index>

Build an unnamed index from a column (for set_index): a Datetime column becomes a DatetimeIndex, an I64 column an Int64Index, a Str column a string index. Float / bool columns are not valid labels.

pub fn from_column_tz(col: &Column, tz: Tz) -> Result<Index>

Build an unnamed index from a column, tagging a Datetime column with tz (otherwise the tz is ignored).

An I64 / Str column carrying volas.NA is rejected: an int/str index has no missing-label representation, so building one would silently turn each NA into its physical placeholder (0 / "") — an ordinary label a .loc lookup can match (C2/C4). Datetime is the one nullable index kind: NaT is a physical sentinel inside the label vector itself, rendered as NaT and sorted last.

pub fn tz(&self) -> Tz

The timezone of a Datetime index (Tz::Naive for every other kind).

pub fn with_tz(self, tz: Tz) -> Index

Return this index with its timezone set (no-op for a non-datetime index); the name is preserved.

pub fn len(&self) -> usize

Number of labels.

pub fn label_at(&self, i: usize) -> Label

The label at position i (for membership tests like drop).

pub fn is_empty(&self) -> bool

Whether the index is empty.

pub fn to_i64_labels(&self) -> Vec<i64>

Materialize the numeric labels as i64. Numeric indexes only — string indexes are handled by their own paths (label_slice / append guard).

pub fn slice(&self, start: usize, end: usize) -> Index

A [start, end) slice (the name and a datetime tz are preserved).

pub fn take(&self, idx: &[usize]) -> Index

Gather the given positions (the name and a datetime tz are preserved).

pub fn label_eq(&self, other: &Index) -> bool

Value equality of the labels (pandas .equals index semantics): a RangeIndex equals the same integer labels materialized as Int64, but an integer index never equals a datetime or string index. The index name and a datetime tz (display metadata) are ignored.

pub fn argsort(&self, ascending: bool) -> Vec<usize>

The positions that sort the index by label (sort_index). Numeric kinds sort numerically, a string index lexicographically.

pub fn to_column(&self) -> Column

Materialize the labels as a Column (for reset_index).

pub fn append(&self, other: &Index) -> Result<Index>

Concatenate two indexes (extending labels), keeping the left index’s name. Same-kind indexes preserve their kind; mixing numeric kinds yields Int64; mixing a string index with a numeric one is an error.

pub fn extend(&mut self, other: &Index) -> Result<()>

Extend in place by the labels of other — the amortized-O(1) counterpart of append, used by the live single-bar hot path; the growing index keeps its own name (so appending an unnamed bar to a named index does not drop the name). Same-kind indexes grow their buffer; a numeric-kind mix collapses to Int64; mixing a string index with a numeric one is an error.

pub fn position_of(&self, label: &Label) -> Option<usize>

Position of the first label exactly equal to label. Returns None if the label’s kind does not match the index’s kind.

pub fn label_slice( &self, lo: Option<&Label>, hi: Option<&Label>, ) -> (usize, usize)

[start, end) positions covering the inclusive label range [lo, hi] (ascending labels; pandas .loc slice semantics). Either bound may be None for open-ended. Numeric indexes compare numerically; a string index compares lexicographically.

Trait Implementations

impl Clone for Index

fn clone(&self) -> Index

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Index

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

Formats the value using the given formatter.

impl PartialEq for Index

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Index