Pandas read_csv() Function

Suraj Joshi Jan 30, 2023
  1. Syntax of pandas.read_csv():
  2. Example Codes: Pandas Read CSV File Using pandas.read_csv() Function
  3. Example Codes:Set usecols Parameter in pandas.read_csv() Function
  4. Example Codes: pandas.read_csv() Function With Header
  5. Example Codes: pandas.read_csv() Function With Skipping Rows
Pandas read_csv() Function

ThePandas read_csv() method reads the specified comma-separated values (CSV) file into DataFrame.

Syntax of pandas.read_csv():

pandas.read_csv(filepath_or_buffer: Union[str, pathlib.Path, IO[~ AnyStr]],
                sep=',',
                delimiter=None,
                header='infer',
                names=None,
                index_col=None,
                usecols=None,
                squeeze=False,
                prefix=None,
                mangle_dupe_cols=True,
                dtype=None,
                engine=None,
                converters=None,
                true_values=None,
                false_values=None,
                skipinitialspace=False,
                skiprows=None,
                skipfooter=0,
                nrows=None,
                na_values=None,
                keep_default_na=True,
                na_filter=True,
                verbose=False,
                skip_blank_lines=True,
                parse_dates=False,
                infer_datetime_format=False,
                keep_date_col=False,
                date_parser=None,
                dayfirst=False,
                cache_dates=True,
                iterator=False,
                chunksize=None,
                compression='infer',
                thousands=None,
                decimal: str='.',
                lineterminator=None,
                quotechar='"',
                quoting=0,
                doublequote=True,
                escapechar=None,
                comment=None,
                encoding=None,
                dialect=None,
                error_bad_lines=True,
                warn_bad_lines=True,
                delim_whitespace=False,
                low_memory=True,
                memory_map=False,
                float_precision=None)

Parameters

filepath_or_buffer location of csv file to be imported
delimiter Delimiter to use for parsing content of csv file
usecols The column names only to be included while forming DataFrame from the csv file.
header which row/rows to use as the column names of header
squeeze returns Pandas series if the parsed data only contains one column.
skiprows which row/rows to skip

Return

Dataframe formed from CSV file with labeled axes.

Example Codes: Pandas Read CSV File Using pandas.read_csv() Function

import pandas as pd
df = pd.read_csv("dataset.csv")
print(df)

Output:

       Country      Item Type Sales Channel Order Priority
0       Tuvalu      Baby Food       Offline              H
1   East Timor           Meat        Online              L
2       Norway      Baby Food        Online              L
3     Portugal      Baby Food        Online              H
4     Honduras         Snacks        Online              L
5  New Zealand         Fruits        Online              H
6     Moldova   Personal Care        Online              L

This method loads the CSV file into the DataFrame. Here, we can use both the absolute and relative paths to provide a file path as an argument to the pandas.read_csv() function.

In this case, the dataset.csv is in the same directory as the program file; this means that you can use the name of the CSV file as a file path.

Example Codes:Set usecols Parameter in pandas.read_csv() Function

import pandas as pd
df = pd.read_csv("dataset.csv",usecols=["Country","Sales Channel","Order Priority"])
print(df)

Output:

       Country Sales Channel Order Priority
0       Tuvalu       Offline              H
1   East Timor        Online              L
2       Norway        Online              L
3     Portugal        Online              H
4     Honduras        Online              L
5  New Zealand        Online              H
6     Moldova         Online              L

In this example, it loads the CSV file into the DataFrame by including only the specified columns in the usecols parameter.

The columns Country, Sales Channel, and Order Priority are only passed as parameters, so they are only included in the DataFrame.

Example Codes: pandas.read_csv() Function With Header

import pandas as pd
df = pd.read_csv("dataset.csv",header=1)
print(df)

Output:

        Tuvalu      Baby Food Offline  H
0   East Timor           Meat  Online  L
1       Norway      Baby Food  Online  L
2     Portugal      Baby Food  Online  H
3     Honduras         Snacks  Online  L
4  New Zealand         Fruits  Online  H
5     Moldova   Personal Care  Online  L

This process loads the CSV file into the DataFrame by setting the first row as a header.

Here, the first row elements serve as the column names for the entire DataFrame.

Example Codes: pandas.read_csv() Function With Skipping Rows

import pandas as pd
df = pd.read_csv("dataset.csv",skiprows=3)
print(df)

Output:

        Norway      Baby Food  Online  L
0     Portugal      Baby Food  Online  H
1     Honduras         Snacks  Online  L
2  New Zealand         Fruits  Online  H
3     Moldova   Personal Care  Online  L

This procedure loads the CSV file into the DataFrame by skipping the first 3 rows.

Author: Suraj Joshi
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Suraj Joshi is a backend software engineer at Matrice.ai.

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