Pandas Series: reindex() function

Last update on April 18 2022 10:51:55 (UTC/GMT +8 hours)

Conform series in Pandas

The reindex() function is used to conform Series to new index with optional filling logic, placing NA/NaN in locations having no value in the previous index.

A new object is produced unless the new index is equivalent to the current one and copy=False.

Syntax:

Series.reindex(self, index=None, **kwargs)

Parameters:

Name	Description	Type/Default Value	Required / Optional
index	New labels / index to conform to, should be specified using keywords. Preferably an Index object to avoid duplicating data	array-like	optional
method	Method to use for filling holes in reindexed DataFrame. Please note: this is only applicable to DataFrames/Series with a monotonically increasing/decreasing index. None (default): don’t fill gaps pad / ffill: propagate last valid observation forward to next valid . backfill / bfill: use next valid observation to fill gap nearest: use nearest valid observations to fill gap	{None, ‘backfill’/’bfill’, ‘pad’/’ffill’, ‘nearest’}	Required
copy	Return a new object, even if the passed indexes are the same.	bool Default Value: True	Required
level	Broadcast across a level, matching Index values on the passed MultiIndex level.	int or name	Required
fill_value	Value to use for missing values. Defaults to NaN, but can be any “compatible” value.	scalar Default Value: np.NaN	Required
limit	Maximum number of consecutive elements to forward or backward fill.	int Default Value: None	Required
tolerance	Maximum distance between original and new labels for inexact matches. The values of the index at the matching locations most satisfy the equation abs(index[indexer] - target) <= tolerance. Tolerance may be a scalar value, which applies the same tolerance to all values, or list-like, which applies variable tolerance per element. List-like includes list, tuple, array, Series, and must be the same size as the index and its dtype must exactly match the index’s type.		optional

Returns: Series with changed index.

Example:

Download the Pandas Series Notebooks from here.

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