Python Pandas Series

A Series is an ordered collection of somewhat-uniform data that can be indexed.

The type is fully specified as pandas.core.series.Series.

Contents

Python Pandas Series

Example

import pandas as pd

pd.Series(["foo", "bar", "baz"])  # 0   foo
                                  # 1   bar
                                  # 2   baz
                                  # dtype: object

Data Model

A Series can be instantiated with any iterable.

Index

By default, a series is indexed by a sequential integer (beginning at 0).

Certain iterables are interpreted as pairs of indices and values.

d = {"First": "foo", "Second": "bar", "Third": "baz"}
s = pd.Series(d)  # First    foo
                  # Second   bar
                  # Third    baz
                  # dtype: object

A second iterable can be specified as explicit indices.

d = ["foo", "bar", "baz"]
i = ["First", "Second", "Third"]
s = pd.Series(d, i)
s = pd.Series(d, index=i)
s = pd.Series(data=d, index=i)

DType

A series without significant consistency of data types with initialize with a dtype of object. Alternatives include:

int64
float64
datetime64
bool
category

Dunder Methods

Series objects support all of the dunder methods implied by a sequence, e.g. len() and sorted().

Attributes

Method	Meaning
`iloc`	indexable accessor of member values
`index`	RangeIndex containing the member indices
`is_unique`	bool representing if all member values are unique
`loc`	indexable accessor of member values
`size`	int count of member values
`values`	numpy.ndarray containing the member values

Methods

These methods return numpy.float64 values unless otherwise specified.

Method	Meaning	Example
`get`	return the value from an index or a default	`s.get("foo", default=None)`
`head`	return a `Series` of the first N member values	`s.head(5)`
`mean`	return mean value
`product`	return product from multiplying all member values
`sort_index`	return a `Series` sorted by indices	`s.sort_index(ascending=True)`
`sort_values`	return a `Series` sorted by values	`s.sort_values(ascending=True)`
`std`	return standard deviation of values
`sum`	return sum from adding all member values
`tail`	return a `Series` of the last N member values	`s.tail(5)`

Note that the get method can take a list of indices to look up. A new Series will be returned if all indices exist, and the singleton default will be returned otherwise.

CategoryRicottone

Python/Pandas/Series