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 = ‘»‘ , lineterminator = 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.
Parameters path_or_buf str, path object, file-like object, or None, default None
String, path object (implementing os.PathLike[str]), or file-like object implementing a write() function. If None, 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 might need to contain a ‘b’ .
Changed in version 1.2.0: Support for binary file objects was introduced.
String of length 1. Field delimiter for the output file.
na_rep str, default ‘’
Missing data representation.
float_format str, Callable, default None
Format string for floating point numbers. If a Callable is given, it takes precedence over other numeric formatting parameters, like decimal.
columns sequence, optional
header bool 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.
index bool, default True
index_label str 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.
mode str, default ‘w’
Python write mode. The available write modes are the same as open() .
encoding str, 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.
compression str or dict, default ‘infer’
For on-the-fly compression of the output data. If ‘infer’ and ‘path_or_buf’ is path-like, then detect compression from the following extensions: ‘.gz’, ‘.bz2’, ‘.zip’, ‘.xz’, ‘.zst’, ‘.tar’, ‘.tar.gz’, ‘.tar.xz’ or ‘.tar.bz2’ (otherwise no compression). Set to None for no compression. Can also be a dict with key ‘method’ set to one of < 'zip' , 'gzip' , 'bz2' , 'zstd' , 'tar' >and other key-value pairs are forwarded to zipfile.ZipFile , gzip.GzipFile , bz2.BZ2File , zstandard.ZstdCompressor or tarfile.TarFile , respectively. As an example, the following could be passed for faster compression and to create a reproducible gzip archive: compression= .
New in version 1.5.0: Added support for .tar files.
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’, ‘bz2’, ‘zstd’, and ‘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 .
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.
quotechar str, default ‘»’
String of length 1. Character used to quote fields.
lineterminator str, 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, ‘\r\n’ for Windows, i.e.).
Changed in version 1.5.0: Previously was line_terminator, changed for consistency with read_csv and the standard library ‘csv’ module.
date_format str, default None
Format string for datetime objects.
doublequote bool, default True
Control quoting of quotechar inside a field.
escapechar str, default None
String of length 1. Character used to escape sep and quotechar when appropriate.
decimal str, default ‘.’
Character recognized as decimal separator. E.g. use ‘,’ for European data.
errors str, default ‘strict’
Specifies how encoding and decoding errors are to be handled. See the errors argument for open() for a full list of options.
Extra options that make sense for a particular storage connection, e.g. host, port, username, password, etc. For HTTP(S) URLs the key-value pairs are forwarded to urllib.request.Request as header options. For other URLs (e.g. starting with “s3://”, and “gcs://”) the key-value pairs are forwarded to fsspec.open . Please see fsspec and urllib for more details, and for more examples on storage options refer here.
If path_or_buf is None, returns the resulting csv format as a string. Otherwise returns None.
Load a CSV file into a DataFrame.
Write DataFrame to an Excel file.
>>> 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)
To write a csv file to a new folder or nested folder you will first need to create it using either Pathlib or os:
>>> from pathlib import Path >>> filepath = Path('folder/subfolder/out.csv') >>> filepath.parent.mkdir(parents=True, exist_ok=True) >>> df.to_csv(filepath)
>>> import os >>> os.makedirs('folder/subfolder', exist_ok=True) >>> df.to_csv('folder/subfolder/out.csv')
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 = ‘»‘ , lineterminator = 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.
Parameters : path_or_buf str, path object, file-like object, or None, default None
String, path object (implementing os.PathLike[str]), or file-like object implementing a write() function. If None, 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 might need to contain a ‘b’ .
Changed in version 1.2.0: Support for binary file objects was introduced.
String of length 1. Field delimiter for the output file.
na_rep str, default ‘’
Missing data representation.
float_format str, Callable, default None
Format string for floating point numbers. If a Callable is given, it takes precedence over other numeric formatting parameters, like decimal.
columns sequence, optional
header bool 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.
index bool, default True
index_label str 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.
mode , default ‘w’
Forwarded to either open(mode=) or fsspec.open(mode=) to control the file opening. Typical values include:
- ‘w’, truncate the file first.
- ‘x’, exclusive creation, failing if the file already exists.
- ‘a’, append to the end of file if it exists.
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.
compression str or dict, default ‘infer’
For on-the-fly compression of the output data. If ‘infer’ and ‘path_or_buf’ is path-like, then detect compression from the following extensions: ‘.gz’, ‘.bz2’, ‘.zip’, ‘.xz’, ‘.zst’, ‘.tar’, ‘.tar.gz’, ‘.tar.xz’ or ‘.tar.bz2’ (otherwise no compression). Set to None for no compression. Can also be a dict with key ‘method’ set to one of < 'zip' , 'gzip' , 'bz2' , 'zstd' , 'xz' , 'tar' >and other key-value pairs are forwarded to zipfile.ZipFile , gzip.GzipFile , bz2.BZ2File , zstandard.ZstdCompressor , lzma.LZMAFile or tarfile.TarFile , respectively. As an example, the following could be passed for faster compression and to create a reproducible gzip archive: compression= .
New in version 1.5.0: Added support for .tar files.
May be a dict with key ‘method’ as compression mode and other entries as additional compression options if compression mode is ‘zip’.
Passing compression options as keys in dict is supported for compression modes ‘gzip’, ‘bz2’, ‘zstd’, and ‘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 .
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.
quotechar str, default ‘»’
String of length 1. Character used to quote fields.
lineterminator str, 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, ‘\r\n’ for Windows, i.e.).
Changed in version 1.5.0: Previously was line_terminator, changed for consistency with read_csv and the standard library ‘csv’ module.
date_format str, default None
Format string for datetime objects.
doublequote bool, default True
Control quoting of quotechar inside a field.
escapechar str, default None
String of length 1. Character used to escape sep and quotechar when appropriate.
decimal str, default ‘.’
Character recognized as decimal separator. E.g. use ‘,’ for European data.
errors str, default ‘strict’
Specifies how encoding and decoding errors are to be handled. See the errors argument for open() for a full list of options.
storage_options dict, optional
Extra options that make sense for a particular storage connection, e.g. host, port, username, password, etc. For HTTP(S) URLs the key-value pairs are forwarded to urllib.request.Request as header options. For other URLs (e.g. starting with “s3://”, and “gcs://”) the key-value pairs are forwarded to fsspec.open . Please see fsspec and urllib for more details, and for more examples on storage options refer here.
If path_or_buf is None, returns the resulting csv format as a string. Otherwise returns None.
Load a CSV file into a DataFrame.
Write DataFrame to an Excel file.
>>> 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)
To write a csv file to a new folder or nested folder you will first need to create it using either Pathlib or os:
>>> from pathlib import Path >>> filepath = Path('folder/subfolder/out.csv') >>> filepath.parent.mkdir(parents=True, exist_ok=True) >>> df.to_csv(filepath)
>>> import os >>> os.makedirs('folder/subfolder', exist_ok=True) >>> df.to_csv('folder/subfolder/out.csv')