workflows (version 0.1.1)

workflow-extractors: Extract elements of a workflow

Description

These functions extract various elements from a workflow object. If they do not exist yet, an error is thrown.

• pull_workflow_preprocessor() returns either the formula or recipe used for preprocessing.

• pull_workflow_spec() returns the parsnip model specification.

• pull_workflow_fit() returns the parsnip model fit.

• pull_workflow_mold() returns the preprocessed "mold" object returned from hardhat::mold(). It contains information about the preprocessing, including either the prepped recipe or the formula terms object.

• pull_workflow_prepped_recipe() returns the prepped recipe. It is extracted from the mold object returned from pull_workflow_mold().

Usage

pull_workflow_preprocessor(x)
pull_workflow_spec(x)
pull_workflow_fit(x)
pull_workflow_mold(x)
pull_workflow_prepped_recipe(x)

Arguments

x

A workflow

Value

The extracted value from the workflow, x, as described in the description section.

Examples

# NOT RUN {
library(parsnip)
library(recipes)

model <- linear_reg()
model <- set_engine(model, "lm")

recipe <- recipe(mpg ~ cyl + disp, mtcars)
recipe <- step_log(recipe, disp)

base_workflow <- workflow()
base_workflow <- add_model(base_workflow, model)

recipe_workflow <- add_recipe(base_workflow, recipe)
formula_workflow <- add_formula(base_workflow, mpg ~ cyl + log(disp))

fit_recipe_workflow <- fit(recipe_workflow, mtcars)
fit_formula_workflow <- fit(formula_workflow, mtcars)

# The preprocessor is either a recipe or a formula
pull_workflow_preprocessor(recipe_workflow)
pull_workflow_preprocessor(formula_workflow)

# The `spec` is the parsnip spec before it has been fit.
# The `fit` is the fit parsnip model.
pull_workflow_spec(fit_formula_workflow)
pull_workflow_fit(fit_formula_workflow)

# The mold is returned from `hardhat::mold()`, and contains the
# predictors, outcomes, and information about the preprocessing
# for use on new data at `predict()` time.
pull_workflow_mold(fit_recipe_workflow)

# A useful shortcut is to extract the prepped recipe from the workflow
pull_workflow_prepped_recipe(fit_recipe_workflow)

# That is identical to
identical(
  pull_workflow_mold(fit_recipe_workflow)$blueprint$recipe,
  pull_workflow_prepped_recipe(fit_recipe_workflow)
)
# }