pandas.DataFrame.to_csv

DataFrame.to_csv(path_or_buf=None, sep=',', na_rep='', float_format=None, columns=None, header=True, index=True, index_label=None, mode='w', encoding=None, compression='infer', quoting=None, quotechar='"', line_terminator=None, chunksize=None, date_format=None, doublequote=True, escapechar=None, decimal='.', errors='strict', storage_options=None)[source]

Write object to a comma-separated values (csv) file.

Changed in version 0.24.0: The order of arguments for Series was changed.

Parameters
path_or_bufstr or file handle, default None

File path or object, if None is provided the result is returned as a string. If a non-binary file object is passed, it should be opened with newline=’’, disabling universal newlines. If a binary file object is passed, mode needs to contain a ‘b’.

Changed in version 0.24.0: Was previously named “path” for Series.

Changed in version 1.2.0: Support for binary file objects was introduced.

sepstr, default ‘,’

String of length 1. Field delimiter for the output file.

na_repstr, default ‘’

Missing data representation.

float_formatstr, default None

Format string for floating point numbers.

columnssequence, optional

Columns to write.

headerbool or list of str, default True

Write out the column names. If a list of strings is given it is assumed to be aliases for the column names.

Changed in version 0.24.0: Previously defaulted to False for Series.

indexbool, default True

Write row names (index).

index_labelstr or sequence, or False, default None

Column label for index column(s) if desired. If None is given, and header and index are True, then the index names are used. A sequence should be given if the object uses MultiIndex. If False do not print fields for index names. Use index_label=False for easier importing in R.

modestr

Python write mode, default ‘w’.

encodingstr, optional

A string representing the encoding to use in the output file, defaults to ‘utf-8’. encoding is not supported if path_or_buf is a non-binary file object.

compressionstr or dict, default ‘infer’

If str, represents compression mode. If dict, value at ‘method’ is the compression mode. Compression mode may be any of the following possible values: {‘infer’, ‘gzip’, ‘bz2’, ‘zip’, ‘xz’, None}. If compression mode is ‘infer’ and path_or_buf is path-like, then detect compression mode from the following extensions: ‘.gz’, ‘.bz2’, ‘.zip’ or ‘.xz’. (otherwise no compression). If dict given and mode is one of {‘zip’, ‘gzip’, ‘bz2’}, or inferred as one of the above, other entries passed as additional compression options.

Changed in version 1.0.0: May now be a dict with key ‘method’ as compression mode and other entries as additional compression options if compression mode is ‘zip’.

Changed in version 1.1.0: Passing compression options as keys in dict is supported for compression modes ‘gzip’ and ‘bz2’ as well as ‘zip’.

Changed in version 1.2.0: Compression is supported for binary file objects.

Changed in version 1.2.0: Previous versions forwarded dict entries for ‘gzip’ to gzip.open instead of gzip.GzipFile which prevented setting mtime.

quotingoptional constant from csv module

Defaults to csv.QUOTE_MINIMAL. If you have set a float_format then floats are converted to strings and thus csv.QUOTE_NONNUMERIC will treat them as non-numeric.

quotecharstr, default ‘"’

String of length 1. Character used to quote fields.

line_terminatorstr, optional

The newline character or character sequence to use in the output file. Defaults to os.linesep, which depends on the OS in which this method is called (‘n’ for linux, ‘rn’ for Windows, i.e.).

Changed in version 0.24.0.

chunksizeint or None

Rows to write at a time.

date_formatstr, default None

Format string for datetime objects.

doublequotebool, default True

Control quoting of quotechar inside a field.

escapecharstr, default None

String of length 1. Character used to escape sep and quotechar when appropriate.

decimalstr, default ‘.’

Character recognized as decimal separator. E.g. use ‘,’ for European data.

errorsstr, default ‘strict’

Specifies how encoding and decoding errors are to be handled. See the errors argument for open() for a full list of options.

New in version 1.1.0.

storage_optionsdict, optional

Extra options that make sense for a particular storage connection, e.g. host, port, username, password, etc., if using a URL that will be parsed by fsspec, e.g., starting “s3://”, “gcs://”. An error will be raised if providing this argument with a local path or a file-like buffer. See the fsspec and backend storage implementation docs for the set of allowed keys and values.

New in version 1.2.0.

Returns
None or str

If path_or_buf is None, returns the resulting csv format as a string. Otherwise returns None.

See also

read_csv

Load a CSV file into a DataFrame.

to_excel

Write DataFrame to an Excel file.

Examples

>>> df = pd.DataFrame({'name': ['Raphael', 'Donatello'],
...                    'mask': ['red', 'purple'],
...                    'weapon': ['sai', 'bo staff']})
>>> df.to_csv(index=False)
'name,mask,weapon\nRaphael,red,sai\nDonatello,purple,bo staff\n'

Create ‘out.zip’ containing ‘out.csv’

>>> compression_opts = dict(method='zip',
...                         archive_name='out.csv')  
>>> df.to_csv('out.zip', index=False,
...           compression=compression_opts)