Align two objects on their axes with the specified join method.
Join method is specified for each axis Index.
Align on index (0), columns (1), or both (None).
Broadcast across a level, matching Index values on the
passed MultiIndex level.
Always returns new objects. If copy=False and no reindexing is
required then original objects are returned.
Value to use for missing values. Defaults to NaN, but can be any
Method to use for filling holes in reindexed Series:
pad / ffill: propagate last valid observation forward to next valid.
backfill / bfill: use NEXT valid observation to fill gap.
If method is specified, this is the maximum number of consecutive
NaN values to forward/backward fill. In other words, if there is
a gap with more than this number of consecutive NaNs, it will only
be partially filled. If method is not specified, this is the
maximum number of entries along the entire axis where NaNs will be
filled. Must be greater than 0 if not None.
Filling axis, method and limit.
Broadcast values along this axis, if aligning two objects of