Convert Pandas to CSV without index
As you know, an index can be thought of as a reference point used to store and access records in a DataFrame. They are unique for each row and usually range from 0 to the last row of the DataFrame, but we can also have serial numbers, dates, and other unique columns as indexes for DataFrames.
But sometimes when exporting or reading files, users may not need this extra index column. The following DataFrame will illustrate this problem more clearly.
import pandas as pd
df = pd.DataFrame([[6, 7, 8], [9, 12, 14], [8, 10, 6]], columns=["a", "b", "c"])
print(df)
Output:
a b c
0 6 7 8
1 9 12 14
2 8 10 6
As you can see, we added an extra index to the DataFrame, which the user can avoid when saving it to a file. If we want to convert this DataFrame into a CSV file without an index column, we can do so by setting to to_csv()in the function .indexFalse
Example code.
import pandas as pd
df = pd.DataFrame([[6, 7, 8], [9, 12, 14], [8, 10, 6]], columns=["a", "b", "c"])
print(df)
df.to_csv("data2.csv", index=False)
Output:
a b c
0 6 7 8
1 9 12 14
2 8 10 6
As you can see from the output, the DataFrame does have an index, but since we indexset the parameter to False, the exported CSV file does not have the extra column.
If we export a file with an extra index column (without indexsetting the parameter to False), and then try to read it, we will get a strange extra column.
import pandas as pd
df = pd.DataFrame([[6, 7, 8], [9, 12, 14], [8, 10, 6]], columns=["a", "b", "c"])
print(df)
df.to_csv("data2.csv")
df_new = pd.read_csv("data2.csv")
print(df_new)
Output:
a b c
0 6 7 8
1 9 12 14
2 8 10 6
Unnamed: 0 a b c
0 0 6 7 8
1 1 9 12 14
2 2 8 10 6
As you can see, df_newthe DataFrame has an extra Unnamedcolumn.
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