The dot() method is used to compute the dot product between DataFrames or Series. DataFrame.dot() from DataFrame class is used to take the dot product of two DataFrames or DataFrame and Series.
Note: Adot()works like amul()function, but instead of returning multiplication separately, it returns the sum of multiplied values at each row or index.
# SignatureDataFrame.dot(other)
It takes the following argument value:
other: Another object of DataFrame or Series or array-like to compute dot product.It returns either Series or DataFrame.
other is Series, it returns series after simple matrix dot product.other is DataFrame, it returns DataFrame after dot product.Let's discuss different scenarios with some coding examples. Here we have listed some commonly used cases:
DataFramesDataFrame and SeriesIn this code, we'll take two DataFrame of the same dimensions and evaluate their dot product.
# importing pandas module as alias pdimport pandas as pd# Creating a DataFramedf1 = pd.DataFrame([[0, 1, -2, -1],[0, 1, None, 1],[1, 3, 1, -1],[1, 1, 6, 1]])# Creating a DataFramedf2 = pd.DataFrame([[5, 3, 6, 4],[11, 3, 4, 3],[4, 3, 8, 3],[5, None, 2, 8]])# Calculating dot productprint(df1.dot(df2))
DataFrame df1 that contains four DataFrame df2 that contains four observations.df1.dot(df2) to evaluate dot product in return.In this code snippet, we'll create a pandas DataFrame and Series object to calculate their dot product.
# importing pandas as pdimport pandas as pd# Creating the dataframedf = pd.DataFrame([[5, 3, 6, 4],[11, None, 4, 3],[4, 3, 8, None],[5, 4, 2, 8]])# Creating a seriesseries = pd.Series([1, 1, 2, 1])# Print the dot product between DataFrame and Seriesprint(df.dot(series))
DataFrame df that contains four observations.Series to get Pandas series object of four values.df.dot(series) to get dot product between DataFrame and series.