Parametrization¶

Note

This is a quick reference, for an in-depth tutorial, click here.

To parametrize your pipeline, create an env.yaml:

some_param: some_value
another_param: 42

Then use {{placeholders}} in your pipeline.yaml file:

tasks:
  - source: scripts/plot.py
    product: products/plot.ipynb
    params:
      some_param: '{{some_param}}'

When executing your pipeline, scripts/plot.py receives some_param="some_value".

You can use {{placeholders}}. The most common use case are tasks[*].params (just like the example above), and tasks[*].product, to change the output location, or you can use both at the same time:

tasks:
  - source: scripts/plot.py
    product: 'products/{{some_param}}/plot.ipynb'
    params:
      some_param: '{{some_param}}'

Switching from the command line¶

Ploomber recognizes {{placeholders}} and adds command-line arguments to change their value, to see a list of available placeholders:

ploomber build --help

Dynamic parameters¶

Parameters declared in env.yaml are static (they can only change in value by editing the env.yaml file or via the command-line); however, you can use the Python API to create dynamic parameters whose values are determined at runtime, check out this example.

Contents

Parametrization¶

Switching from the command line¶

Dynamic parameters¶