Pandas DataFrame: to_csv() function

Last update on August 19 2022 21:50:33 (UTC/GMT +8 hours)

DataFrame - to_csv() function

The to_csv() function is used to write object to a comma-separated values (csv) file.

Syntax:

DataFrame.to_csv(self, 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='.')

Parameters:

Name	Description	Type / Default Value	Required / Optional
path_or_buf	File path or object, if None is provided the result is returned as a string. If a file object is passed it should be opened with newline=’’, disabling universal newlines. Changed in version 0.24.0: Was previously named “path” for Series.	str or file handle Default Value: None	Required
sep	String of length 1. Field delimiter for the output file.	str Default Value: ','	Required
na_rep	Missing data representation.	str Default Value: ''	Required
float_format	Format string for floating point numbers.	str Default Value: None	Required
columns	Columns to write.	sequence	Optional
header	Write out the column names. If a list of strings is given it is assumed to be aliases for the column names.	bool or list of str Default Value: True	Required
index	Write row names (index).	bool Default Value: True	Required
index_label	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.	str or sequence, or False Default Value: None	Required
mode	Python write mode, default 'w'.	str	Required
encoding	A string representing the encoding to use in the output file, defaults to ‘utf-8’.	str	Optional
compression	Compression mode among the following possible values: {'infer', 'gzip', 'bz2', 'zip', 'xz', None}. If ‘infer’ and path_or_buf is path-like, then detect compression from the following extensions: '.gz', '.bz2', '.zip' or '.xz'. (otherwise no compression).	str Default Value: 'infer'	Required
quoting	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.	optional constant from csv module	Required
quotechar	String of length 1. Character used to quote fields.	str Default Value: ‘”’	Required
line_terminator	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.).	str	Optional
chunksize	Rows to write at a time.	int Default Value: None	Required
date_format	Format string for datetime objects.	str Default Value: None	Required
doublequote	Control quoting of quotechar inside a field.	bool Default Value: True	Required
escapechar	String of length 1. Character used to escape sep and quotechar when appropriate.	str Default Value: None	Required
decimal	Character recognized as decimal separator. E.g. use ',' for European data.	str Default Value: ','	Required

Returns: None or str
If path_or_buf is None, returns the resulting csv format as a string. Otherwise returns None.

Example:

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