Rename columns in datasets programmatically

Renaming columns in a dataset programmatically can be done easily using various libraries in Python, such as pandas. Here’s how you can do it step-by-step:

1. Using pandas to Rename Columns

If you’re working with a DataFrame, pandas provides a simple way to rename columns.

Example Code:

python
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import pandas as pd

# Create a sample DataFrame
data = {
    'OldName1': [1, 2, 3],
    'OldName2': [4, 5, 6]
}
df = pd.DataFrame(data)

# Display the original DataFrame
print("Original DataFrame:")
print(df)

# Rename columns
df.rename(columns={'OldName1': 'NewName1', 'OldName2': 'NewName2'}, inplace=True)

# Display the modified DataFrame
print("nDataFrame after renaming columns:")
print(df)

2. Using set_axis() for Renaming

You can also use the set_axis() method to rename columns by passing a list of new column names.

Example Code:

python
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# Set new column names
df.columns = ['NewName1', 'NewName2']

# Display the modified DataFrame
print("nDataFrame after renaming columns:")
print(df)

3. Renaming Columns Dynamically

If you need to rename columns dynamically, for example, replacing spaces with underscores or making them lowercase, you can use the following approach:

Example Code:

python
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# Dynamically rename columns by making them lowercase and replacing spaces
df.columns = [col.lower().replace(' ', '_') for col in df.columns]

# Display the modified DataFrame
print("nDataFrame after dynamic renaming of columns:")
print(df)

4. Renaming Specific Columns

If you only want to rename specific columns without affecting others, you can target only the columns you need by referencing them individually or with conditions.

Example Code:

python
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# Rename a single column
df.rename(columns={'NewName1': 'UpdatedName1'}, inplace=True)

# Display the modified DataFrame
print("nDataFrame after renaming one column:")
print(df)

5. Using a Dictionary for Bulk Renaming

For a large DataFrame, you can use a dictionary to map old column names to new ones, which is especially useful if you have many columns to rename.

Example Code:

python
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# Dictionary for bulk renaming
columns_map = {
    'NewName1': 'Renamed1',
    'NewName2': 'Renamed2'
}

# Apply the renaming
df.rename(columns=columns_map, inplace=True)

# Display the modified DataFrame
print("nDataFrame after bulk renaming columns:")
print(df)

By using any of these methods, you can easily rename columns programmatically in your datasets.