colour.io.tabular Module¶

CSV Tabular Data Input / Output¶

Defines various input / output objects for CSV tabular data files:

• read_spectral_data_from_csv_file()
• read_spds_from_csv_file()
• write_spds_to_csv_file()

colour.io.tabular.read_spectral_data_from_csv_file(path, delimiter=u', ', fields=None, default=0)[source]¶

Reads the spectral data from given CSV file in the following form:

390, 4.15003E-04, 3.68349E-04, 9.54729E-03 395, 1.05192E-03, 9.58658E-04, 2.38250E-02 400, 2.40836E-03, 2.26991E-03, 5.66498E-02 ... 830, 9.74306E-07, 9.53411E-08, 0.00000

and returns it as an OrderedDict of dict as follows:

OrderedDict([ (‘field’, {‘wavelength’: ‘value’, ..., ‘wavelength’: ‘value’}), ..., (‘field’, {‘wavelength’: ‘value’, ..., ‘wavelength’: ‘value’})])

Parameters:	path (unicode) – Absolute CSV file path. delimiter (unicode, optional) – CSV file content delimiter. fields (array_like, optional) – CSV file spectral data fields names. If no value is provided the first line of the file will be used as spectral data fields names. default (numeric, optional) – Default value for fields row with missing value.
Returns:	CSV file content.
Return type:	OrderedDict
Raises:	RuntimeError – If the CSV spectral data file doesn’t define the appropriate fields.

Notes

• A CSV spectral data file should define at least define two fields: one for the wavelengths and one for the associated values of one spectral power distribution.
• If no value is provided for the fields names, the first line of the file will be used as spectral data fields names.

Examples

>>> import os
>>> from pprint import pprint
>>> csv_file = os.path.join(
...     os.path.dirname(__file__),
...     'tests',
...     'resources',
...     'colorchecker_n_ohta.csv')
>>> spds_data = read_spectral_data_from_csv_file(csv_file)
>>> pprint(list(spds_data.keys()))
['1',
 '2',
 '3',
 '4',
 '5',
 '6',
 '7',
 '8',
 '9',
 '10',
 '11',
 '12',
 '13',
 '14',
 '15',
 '16',
 '17',
 '18',
 '19',
 '20',
 '21',
 '22',
 '23',
 '24']

colour.io.tabular.read_spds_from_csv_file(path, delimiter=u', ', fields=None, default=0)[source]¶

Reads the spectral data from given CSV file and return its content as an OrderedDict of colour.colorimetry.spectrum.SpectralPowerDistribution classes.

Parameters:	path (unicode) – Absolute CSV file path. delimiter (unicode, optional) – CSV file content delimiter. fields (array_like, optional) – CSV file spectral data fields names. If no value is provided the first line of the file will be used for as spectral data fields names. default (numeric) – Default value for fields row with missing value.
Returns:	colour.colorimetry.spectrum.SpectralPowerDistribution classes of given CSV file.
Return type:	OrderedDict

Examples

>>> import os
>>> from pprint import pprint
>>> csv_file = os.path.join(
...     os.path.dirname(__file__),
...     'tests',
...     'resources',
...     'colorchecker_n_ohta.csv')
>>> spds = read_spds_from_csv_file(csv_file)
>>> pprint(tuple(spds.items()))  
(('1',
  <...SpectralPowerDistribution object at 0x...>),
 ('2',
  <...SpectralPowerDistribution object at 0x...>),
 ('3',
  <...SpectralPowerDistribution object at 0x...>),
 ('4',
  <...SpectralPowerDistribution object at 0x...>),
 ('5',
  <...SpectralPowerDistribution object at 0x...>),
 ('6',
  <...SpectralPowerDistribution object at 0x...>),
 ('7',
  <...SpectralPowerDistribution object at 0x...>),
 ('8',
  <...SpectralPowerDistribution object at 0x...>),
 ('9',
  <...SpectralPowerDistribution object at 0x...>),
 ('10',
  <...SpectralPowerDistribution object at 0x...>),
 ('11',
  <...SpectralPowerDistribution object at 0x...>),
 ('12',
  <...SpectralPowerDistribution object at 0x...>),
 ('13',
  <...SpectralPowerDistribution object at 0x...>),
 ('14',
  <...SpectralPowerDistribution object at 0x...>),
 ('15',
  <...SpectralPowerDistribution object at 0x...>),
 ('16',
  <...SpectralPowerDistribution object at 0x...>),
 ('17',
  <...SpectralPowerDistribution object at 0x...>),
 ('18',
  <...SpectralPowerDistribution object at 0x...>),
 ('19',
  <...SpectralPowerDistribution object at 0x...>),
 ('20',
  <...SpectralPowerDistribution object at 0x...>),
 ('21',
  <...SpectralPowerDistribution object at 0x...>),
 ('22',
  <...SpectralPowerDistribution object at 0x...>),
 ('23',
  <...SpectralPowerDistribution object at 0x...>),
 ('24',
  <...SpectralPowerDistribution object at 0x...>))

colour.io.tabular.write_spds_to_csv_file(spds, path, delimiter=u', ', fields=None)[source]¶

Writes the given spectral power distributions to given CSV file.

Parameters:	spds (dict) – Spectral power distributions to write. path (unicode) – Absolute CSV file path. delimiter (unicode, optional) – CSV file content delimiter. fields (array_like, optional) – CSV file spectral data fields names. If no value is provided the order of fields will be the one defined by the sorted spectral power distributions dict.
Returns:	Definition success.
Return type:	bool
Raises:	RuntimeError – If the given spectral power distributions have different shapes.