staircase.core.arrays.accessor.StairsAccessor.limit

StairsAccessor.limit(x, side='right')

Takes a collection of Stairs instances and evaluates their limits across a set of points.

Technically the results of this function should be considered as \(\lim_{x \to z^{-}} f(x)\) or \(\lim_{x \to z^{+}} f(x)\), when side = ‘left’ or side = ‘right’ respectively. See A note on interval endpoints for an explanation.

Parameters:

xscalar or vector data

The points at which to sample the Stairs instances. Must belong to the step function domain.

side{‘left’, ‘right’}, default ‘right’

if points where step changes occur do not coincide with x then this parameter has no effect. Where a step changes occurs at a point given by x, this parameter determines if the step function is evaluated at the interval to the left, or the right.

Returns:

pandas.DataFrame

A dataframe, where rows correspond to the Stairs instances in the pandas.Series. and columns correspond to the points in x. The dataframe will have the same index as the Series.

See also

staircase.limit(), staircase.StairsArray.limit(), staircase.core.arrays.accessor.StairsAccessor.sample()

Examples

>>> import staircase as sc
>>> stairs = pd.Series([s2, s3], dtype="Stairs")
>>> [s2.closed, s3.closed]
["left", "left]

>>> stairs.sc.limit([2,3,4], side="left"))
     2    3    4
0  0.5  0.0 -1.0
1  1.0  NaN  1.0

>>> stairs.sc.limit([2,3,4], side="right"))
     2    3    4
0  0.0 -1.0 -1.0
1  0.0  NaN -1.0