Pandas DataFrame: Difference between revisions

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=Index=
=Index=


By default, the DataFrame gets a [[RangeIndex]]
By default, the DataFrame gets a [[Pandas_Concepts#RangeIndex|RangeIndex]]


=Create a DataFrame=
=Create a DataFrame=

Revision as of 18:52, 8 October 2023

External

Internal

Overview

A DataFrame is a two-dimensional data structure with columns of potentially different types. The data structure also contains labeled axes, for both rows and columns.

Can be thought of as a dict-like container for Series objects, where each column is a Series. The dimensionality of the DataFrame is given by its shape property.

Shape

shape is a property of the DataFrame, containing a tuple that returns the dimensionality of the DataFrame: rows, columns.

Index

By default, the DataFrame gets a RangeIndex

Create a DataFrame

Create a DataFrame from a CSV File

Accessing Elements of a DataFrame

iloc[]

A property that allows integer-based access (indexing). The location is specified as a 0-based index position. The property accepts a wide variety of arguments.

Used in the following situations:

Extract a Series from the DataFrame

iloc[] can be used to extract a series from the DataFrame. The first argument is a slice specifying the series indexes, : to extract the entire series, and the second argument specifies the column index in the DataFrame. The Series gets a default RangeIndex:

df = ...
# extract a series corresponding to DataFrame column 0
s = df.iloc[:,0]

loc[]

A property that allows label-based access (indexing).

squeeze()

[]

Operations on DataFrames