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How to change the order of DataFrame columns?

python
pandas
dataframe
functions
Nikita BarsukovbyNikita Barsukov·Sep 7, 2024
TLDR

Rearrange pandas DataFrame columns by passing a new column order list to the square brackets []:

# Fancy dinner party? Get 'A', 'B', and 'C' in the right order! df = df[['C', 'A', 'B']] # Now it's a party for 'C', 'A', 'B'

Bringing key columns front and center

Make your star column take the lead with this magic trick:

# 'mean' has stage fright? Get it first in line! df.insert(0, 'mean', df.pop('mean'))

Using an older version of pandas (below 1.3)? Fear not and run this line instead:

# Who needs time machines when you have different Panda versions? df.insert(0, 'mean', df['mean']) df = df.drop(columns=['mean'], axis=1)

Juggling columns like a pro

Need to rotate columns like a revolving sushi bar? Well, here you go:

# Your DataFrames will thank you for their new positions! cols = list(df.columns) df = df[cols[-1:] + cols[:-1]] # Take a bow 'mean', you're the new starter!

Be cool, use [] and avoid the outdated ix.

Adapting to dynamic orders

For those cases when column order depends on runtime conditions, use this dynamic piece of code:

#DynamicDay? Adapt on the fly! desired_first_col = 'mean' df = df.reindex(columns=[desired_first_col] + [col for col in df.columns if col != desired_first_col])

Expert level column shuffling

Handling complex reorders

For those tricky times when a single move won't cut it:

# Hogwarts hadn't such a complex order! cols = ['mean', 'std', 'max', 'A', 'B'] df = df[cols] # Now the DataFrame looks like a well-done spell!

Dodging ordering pitfalls

Always verify the upcoming order to avoid repeating or missing columns:

# Asserting order: like looking where you step...but for DataFrames! assert len(cols) == len(df.columns) and len(set(cols)) == len(df.columns)

Keeping original order with a sprinkle of change

Modify column order without losing the original sensation:

# We keep it original here but with some added spice! col_to_front = 'mean' new_cols = [col_to_front] + [col for col in df.columns if col != col_to_front] df = df[new_cols]

Mastering column rearrangement in pandas

The art of pop() and insert()

Here's how to extract a column and insert it back to your desired place:

# Playing 'Hide and Seek' with DataFrames! mean_col = df.pop('mean') df.insert(0, 'mean', mean_col)

Aligning semantic flow

For that extra clarity, place columns according to their logical relationship.

Efficient tricks for column reordering

Trim your columns reordering to fewer lines of code:

# We keep things short and sweet here! df = df[new_cols]

Always ensure there are no mismatches or missing columns!