Struct Expanding 

pub struct Expanding<'a> { /* private fields */ }

Expanding window aggregation over a Series.

Created by Series::expanding(). All prior elements are included in each window computation.

Implementations

impl Expanding<'_>

pub fn sum(&self) -> Result<Series, FrameError>

Expanding sum.

Matches pd.Series.expanding(min_periods).sum(). Empty windows (no non-missing values observed yet) emit Null(NaN) when min_periods >= 1; if the caller explicitly sets min_periods=0 an empty window still returns 0.0 (pandas conventional empty-sum identity).

pub fn mean(&self) -> Result<Series, FrameError>

Expanding mean.

Matches pd.Series.expanding(min_periods).mean(). Empty windows return Null(NaN) regardless of min_periods — mean of an empty set is undefined (pandas emits NaN, not 0/0).

pub fn min(&self) -> Result<Series, FrameError>

Expanding minimum.

pub fn max(&self) -> Result<Series, FrameError>

Expanding maximum.

pub fn std(&self) -> Result<Series, FrameError>

Expanding sample standard deviation (ddof=1).

pub fn var(&self) -> Result<Series, FrameError>

Expanding sample variance (ddof=1).

pub fn median(&self) -> Result<Series, FrameError>

Expanding median.

pub fn apply<F>(&self, func: F) -> Result<Series, FrameError>

where F: Fn(&[f64]) -> f64,

Apply a custom function over the expanding window.

Matches series.expanding().apply(func).

pub fn count(&self) -> Result<Series, FrameError>

Expanding count of non-null values.

Matches series.expanding().count().

pub fn quantile(&self, q: f64) -> Result<Series, FrameError>

Expanding quantile.

Matches series.expanding().quantile(q).

pub fn skew(&self) -> Result<Series, FrameError>

Expanding skewness (bias=False, Fisher’s definition).

Matches pd.Series.expanding().skew().

pub fn kurt(&self) -> Result<Series, FrameError>

Expanding excess kurtosis (Fisher’s definition, bias=False).

Matches pd.Series.expanding().kurt().

pub fn kurtosis(&self) -> Result<Series, FrameError>

Alias for kurt() — pandas exposes both spellings on Series.expanding aggregations.

pub fn corr(&self, other: &Series) -> Result<Series, FrameError>

Expanding Pearson correlation with another Series.

Matches pd.Series.expanding().corr(other). At each position, correlates all prior (and current) aligned pairs that have non-null numeric values in both series. Returns NaN until min_periods and at least two valid pairs are observed, and when either sample standard deviation is zero.

pub fn cov(&self, other: &Series) -> Result<Series, FrameError>

Expanding sample covariance (ddof=1) with another Series.

Matches pd.Series.expanding().cov(other). At each position, the covariance is computed over all aligned pairs where both values are non-null and numeric.

pub fn sem(&self) -> Result<Series, FrameError>

Expanding standard error of the mean.

Matches series.expanding().sem().

pub fn rank( &self, method: &str, ascending: bool, na_option: &str, ) -> Result<Series, FrameError>

Rank the current observation against all observations seen so far.

Matches series.expanding().rank().

pub fn agg(&self, funcs: &[&str]) -> Result<DataFrame, FrameError>

Aggregate with multiple functions, returning a DataFrame.

Matches series.expanding().agg(['sum', 'mean']).

pub fn aggregate(&self, funcs: &[&str]) -> Result<DataFrame, FrameError>

pandas alias for Self::agg.

Matches series.expanding().aggregate([...]).

pub fn exclusions(&self) -> Vec<String>

Frozenset-style label set excluded from this expanding window.

Series expanding windows have no excluded columns.

pub fn ndim(&self) -> usize

Number of dimensions of the underlying object. Series expanding is 1D.