kedro_datasets.matplotlib.MatplotlibWriter

class kedro_datasets.matplotlib.MatplotlibWriter(*, filepath, fs_args=None, credentials=None, save_args=None, version=None, overwrite=False, metadata=None)[source]

MatplotlibWriter saves one or more Matplotlib objects as image files to an underlying filesystem (e.g. local, S3, GCS).

Example usage for the YAML API:

output_plot:
  type: matplotlib.MatplotlibWriter
  filepath: data/08_reporting/output_plot.png
  save_args:
    format: png

Example usage for the Python API:

 import matplotlib.pyplot as plt
 from kedro_datasets.matplotlib import MatplotlibWriter

 fig = plt.figure()
 plt.plot([1, 2, 3])  
[<matplotlib.lines.Line2D object at 0x...>]
 plot_writer = MatplotlibWriter(filepath=tmp_path / "data/08_reporting/output_plot.png")
 plt.close()
 plot_writer.save(fig)

Example saving a plot as a PDF file:

 import matplotlib.pyplot as plt
 from kedro_datasets.matplotlib import MatplotlibWriter

 fig = plt.figure()
 plt.plot([1, 2, 3])  
[<matplotlib.lines.Line2D object at 0x...>]
 pdf_plot_writer = MatplotlibWriter(
...     filepath=tmp_path / "data/08_reporting/output_plot.pdf", save_args={"format": "pdf"}
... )
 plt.close()
 pdf_plot_writer.save(fig)

Example saving multiple plots in a folder, using a dictionary:

 import matplotlib.pyplot as plt
 from kedro_datasets.matplotlib import MatplotlibWriter

 plots_dict = {}
 for colour in ["blue", "green", "red"]:
...     plots_dict[f"{colour}.png"] = plt.figure()
...     plt.plot([1, 2, 3], color=colour)
...
[<matplotlib.lines.Line2D object at 0x...>]
[<matplotlib.lines.Line2D object at 0x...>]
[<matplotlib.lines.Line2D object at 0x...>]
 plt.close("all")
 dict_plot_writer = MatplotlibWriter(filepath=tmp_path / "data/08_reporting/plots")
 dict_plot_writer.save(plots_dict)

Example saving multiple plots in a folder, using a list:

 import matplotlib.pyplot as plt
 from kedro_datasets.matplotlib import MatplotlibWriter

 plots_list = []
 for i in range(5):  
...     plots_list.append(plt.figure())
...     plt.plot([i, i + 1, i + 2])
...
[<matplotlib.lines.Line2D object at 0x...>]
[<matplotlib.lines.Line2D object at 0x...>]
[<matplotlib.lines.Line2D object at 0x...>]
[<matplotlib.lines.Line2D object at 0x...>]
[<matplotlib.lines.Line2D object at 0x...>]
 plt.close("all")
 list_plot_writer = MatplotlibWriter(filepath=tmp_path / "data/08_reporting/plots")
 list_plot_writer.save(plots_list)

Attributes

DEFAULT_SAVE_ARGS

Methods

exists()

Checks whether a data set's output already exists by calling the provided _exists() method.

from_config(name, config[, load_version, ...])

Create a data set instance using the configuration provided.

load()

Loads data by delegation to the provided load method.

preview()

Generates a preview of the matplotlib dataset as a base64 encoded image.

release()

Release any cached data.

resolve_load_version()

Compute the version the dataset should be loaded with.

resolve_save_version()

Compute the version the dataset should be saved with.

save(data)

Saves data by delegation to the provided save method.
DEFAULT_SAVE_ARGS: dict[str, Any] = {}
__init__(*, filepath, fs_args=None, credentials=None, save_args=None, version=None, overwrite=False, metadata=None)[source]

Creates a new instance of MatplotlibWriter.

Parameters:

  • filepath (str) – Filepath in POSIX format to save Matplotlib objects to, prefixed with a protocol like s3://. If prefix is not provided, file protocol (local filesystem) will be used. The prefix should be any protocol supported by fsspec.

  • fs_args (Optional[dict[str, Any]]) – Extra arguments to pass into underlying filesystem class constructor (e.g. {“project”: “my-project”} for GCSFileSystem), as well as to pass to the filesystem’s open method through nested key open_args_save. Here you can find all available arguments for open: https://filesystem-spec.readthedocs.io/en/latest/api.html#fsspec.spec.AbstractFileSystem.open All defaults are preserved, except mode, which is set to wb when saving.

  • credentials (Optional[dict[str, Any]]) – Credentials required to get access to the underlying filesystem. E.g. for S3FileSystem it should look like: {‘key’: ‘<id>’, ‘secret’: ‘<key>’}}

  • save_args (Optional[dict[str, Any]]) – Save args passed to plt.savefig. See https://matplotlib.org/api/_as_gen/matplotlib.pyplot.savefig.html

  • version (Optional[Version]) – If specified, should be an instance of kedro.io.core.Version. If its load attribute is None, the latest version will be loaded. If its save attribute is None, save version will be autogenerated.

  • overwrite (bool) – If True, any existing image files will be removed. Only relevant when saving multiple Matplotlib objects at once.

  • metadata (Optional[dict[str, Any]]) – Any arbitrary Any arbitrary metadata. This is ignored by Kedro, but may be consumed by users or external plugins.

exists()

Checks whether a data set’s output already exists by calling the provided _exists() method.

Return type:

bool

Returns:

Flag indicating whether the output already exists.

Raises:

DatasetError – when underlying exists method raises error.

classmethod from_config(name, config, load_version=None, save_version=None)

Create a data set instance using the configuration provided.

Parameters:

  • name (str) – Data set name.

  • config (dict[str, Any]) – Data set config dictionary.

  • load_version (str | None) – Version string to be used for load operation if the data set is versioned. Has no effect on the data set if versioning was not enabled.

  • save_version (str | None) – Version string to be used for save operation if the data set is versioned. Has no effect on the data set if versioning was not enabled.

Return type:

AbstractDataset

Returns:

An instance of an AbstractDataset subclass.

Raises:

DatasetError – When the function fails to create the data set from its config.

load()

Loads data by delegation to the provided load method.

Return type:

TypeVar(_DO)

Returns:

Data returned by the provided load method.

Raises:

DatasetError – When underlying load method raises error.

preview()[source]

Generates a preview of the matplotlib dataset as a base64 encoded image.

Returns:

A base64 encoded string representing the matplotlib plot image.

Return type:

str

release()

Release any cached data.

Raises:

DatasetError – when underlying release method raises error.

Return type:

None

resolve_load_version()

Compute the version the dataset should be loaded with.

Return type:

str | None

resolve_save_version()

Compute the version the dataset should be saved with.

Return type:

str | None

save(data)

Saves data by delegation to the provided save method.

Parameters:

data (TypeVar(_DI)) – the value to be saved by provided save method.

Raises:

  • DatasetError – when underlying save method raises error.

  • FileNotFoundError – when save method got file instead of dir, on Windows.

  • NotADirectoryError – when save method got file instead of dir, on Unix.

Return type:

None