Repository: scikit-learn/scikit-learn
File: examples/release_highlights/plot_release_highlights_1_8_0.py (Python)

Code before:
        y == c, sig.predict_proba(X)[:, i], name="Sigmoid", ax=axes[i], marker="v"
    )
    axes[i].set_title(f"Class {c}")
    axes[i].set_xlabel(None)
    axes[i].set_ylabel(None)
    axes[i].get_legend().remove()
fig.suptitle("Reliability Diagrams per Class")
fig.supxlabel("Mean Predicted Probability")
fig.supylabel("Fraction of Class")
fig.legend(*axes[0].get_legend_handles_labels(), loc=(0.72, 0.5))
plt.subplots_adjust(right=0.7)
_ = fig.show()

# %%
# Linear models improvements
# --------------------------
# There are two main developments going on for linear models: efficiency and API
# changes.
#
# Efficiency of squared error based models with L1 penalty
# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
# The first one is a massive improvement of efficiency, in particular a reduced fit
# time, for squared error based estimators with L1 penalty: `ElasticNet`, `Lasso`,
# `MultiTaskElasticNet`, `MultiTaskLasso` and their CV variants. The fit time
# improvement is mainly achieved by **gap safe screening rules**. They enable the
# coordinate descent solver to set feature coefficients to 0 early and not look at them
# again. The stronger the L1 penalty the earlier features can be excluded from further
# updates.

from time import time

from sklearn.datasets import make_regression
from sklearn.linear_model import ElasticNetCV

X, y = make_regression(n_features=10_000, random_state=0)
model = ElasticNetCV()
tic = time()
model.fit(X, y)
toc = time()
print(f"Fitting ElasticNetCV took {toc - tic:.3} seconds.")

# %%
# API changes in logistic regression
# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
# After the deprecation (version 1.5) and removal (now in 1.8) of the `multi_class`
# parameter in `LogisticRegression` and `LogisticRegressionCV`, the bookkeeping goes
# on. The goal for `LogisticRegressionCV` is to fix types and shapes of a few fitted
# attributes: `C_`, `l1_ratio_`, `coefs_paths_`, `scores_`, `n_iter_`. To ease the
# transition, you can choose between new and old types and shapes with the new and
# temporary parameter `use_legacy_attributes`.


Review comment (performance):
```suggestion
# coordinate descent solver to set feature coefficients to 0 early on and not look at them
```
Not 💯 sure if this is better.

Code after:
    axes[i].set_xlabel(None)
    axes[i].set_ylabel(None)
    axes[i].get_legend().remove()
fig.suptitle("Reliability Diagrams per Class")
fig.supxlabel("Mean Predicted Probability")
fig.supylabel("Fraction of Class")
fig.legend(*axes[0].get_legend_handles_labels(), loc=(0.72, 0.5))
plt.subplots_adjust(right=0.7)
_ = fig.show()

# %%
# Efficiency improvements in linear models
# ----------------------------------------
# The fit time has been massively reduced for squared error based estimators
# with L1 penalty: `ElasticNet`, `Lasso`, `MultiTaskElasticNet`,
# `MultiTaskLasso` and their CV variants. The fit time improvement is mainly
# achieved by **gap safe screening rules**. They enable the coordinate descent
# solver to set feature coefficients to zero early on and not look at them
# again. The stronger the L1 penalty the earlier features can be excluded from
# further updates.

from time import time

from sklearn.datasets import make_regression
from sklearn.linear_model import ElasticNetCV

X, y = make_regression(n_features=10_000, random_state=0)
model = ElasticNetCV()
tic = time()
model.fit(X, y)
toc = time()
print(f"Fitting ElasticNetCV took {toc - tic:.3} seconds.")

# %%
# HTML representation of estimators
# ---------------------------------
# Hyperparameters in the dropdown table of the HTML representation now include
# links to the online documentation. Docstring descriptions are also shown as
# tooltips on hover.

from sklearn.linear_model import LogisticRegression
from sklearn.pipeline import make_pipeline
from sklearn.preprocessing import StandardScaler

clf = make_pipeline(StandardScaler(), LogisticRegression(random_state=0, C=10))

# %%
# Expand the estimator diagram below by clicking on "LogisticRegression" and then on
# "Parameters".

clf