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Pandas ValueError Arrays Must be All Same Length

Learn about the Pandas ValueError Arrays Must be All Same Length and how to fix it?
Submitted by Pranit Sharma, on September 14, 2022

Pandas is a special tool that allows us to perform complex manipulations of data effectively and efficiently. Inside pandas, we mostly deal with a dataset in the form of DataFrame. DataFrames are 2-dimensional data structures in pandas. DataFrames consist of rows, columns, and data.

What is 'ValueError Arrays Must be All Same Length'? Error

Whenever we create a DataFrame, we either create a dictionary or we create a Series.

We sometimes observe this error that pandas ValueError Arrays Must be All Same Length. This error occurs when we do not pass the equal values for a key or equal elements in a Series.

Let us see how this error occurs.

Python code to demonstrate ValueError arrays must be all same length error

# Importing pandas package
import pandas as pd

# Creating a dictionary with 
# unequal elements
d = {
    'A':[1,2,3],
    'B':[4,5,6,7],
    'C':[8]
}

# Creating a DataFrame
df = pd.DataFrame(d)

Output

How to Fix Pandas ValueError arrays must be all same length error

To fix Pandas "ValueError Arrays Must be All Same Length" - Pass equal values for all keys.

Example

# Importing pandas package
import pandas as pd

# Creating a dictionary with 
# equal elements
d = {
    'A':[1,2,3],
    'B':[4,5,6,],
    'C':[7,8,9]
}

# Creating a DataFrame
df = pd.DataFrame(d)

# Display DataFrame
print("Created DataFrame:\n",df)

Output

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