align¶

Defined in fynance.data

align(series, how='outer', fill='ffill')[source]

Align several series onto a common index.

Parameters:

seriesdict of str to PriceSeries: Named series to align.
how{“outer”, “inner”}: outer uses the union of indices, inner the intersection.
fill{“ffill”, None}: Forward-fill (past-only) missing values after an outer align.

Returns:

dict of str to PriceSeries: Series sharing a common index.

Raises:

ValueError: If how is unknown, or if any input series has duplicate index entries. Duplicate timestamps would otherwise be silently collapsed (the index-to-value mapping keeps only the last value), shrinking the series to its unique count without warning.