Removing cells, inputs, or outputs
.. module:: nbconvert.preprocessors
When converting Notebooks into other formats, it is possible to remove parts of a cell, or entire cells, using preprocessors. The notebook will remain unchanged, but the outputs will have certain pieces removed. Here are two primary ways to accomplish this.
Removing pieces of cells using cell tags
The most straightforward way to control which pieces of cells are removed is to use cell tags. These are single-string snippets of metadata that are stored in each cells "tag" field. The :class:`TagRemovePreprocessor` can be used to remove inputs, outputs, or entire cells.
For example, here is a configuration that uses a different tag for removing each part of a cell with the HTMLExporter. In this case, we demonstrate using the nbconvert Python API.
from traitlets.config import Config import nbformat as nbf from nbconvert.exporters import HTMLExporter c = Config() # Configure our tag removal c.TagRemovePreprocessor.remove_cell_tags = ("remove_cell",) c.TagRemovePreprocessor.remove_all_outputs_tags = ('remove_output',) c.TagRemovePreprocessor.remove_input_tags = ('remove_input',) # Configure and run out exporter c.HTMLExporter.preprocessors = ["TagRemovePreprocessor"] HTMLExporter(config=c).from_filename("path/to/mynotebook.ipynb")
Removing cells using Regular Expressions on cell content
Sometimes you'd rather remove cells based on their _content_ rather than their tags. In this case, you can use the :class:`RegexRemovePreprocessor`.
You initalize this preprocessor with a single patterns configuration, which is a list of strings. For each cell, this preprocessor checks whether the cell contents match any of the strings provided in patterns. If the contents match any of the patterns, the cell is removed from the notebook.
For example, execute the following command to convert a notebook to html and remove cells containing only whitespace:
jupyter nbconvert --RegexRemovePreprocessor.patterns="['\s*\Z']" mynotebook.ipynb
The command line argument sets the list of patterns to 's*Z' which matches an arbitrary number of whitespace characters followed by the end of the string.
See https://regex101.com/ for an interactive guide to regular expressions (make sure to select the python flavor). See https://docs.python.org/library/re.html for the official regular expression documentation in python.