what = "all" selects available training, validation, and test pairs for
a regression model, or training and test pairs for a resampled model.
An explicitly requested missing sample is an error. Resampled observations
are pooled in fold order, keeping repeated observations. Pair lengths and
names are checked within each fold before pooling.
Rendering is provided by rtemis.draw::draw_fit(). The API uses draw argument names,
including se, square, equal_axes, and title, and a draw rtemis.draw::Theme.
Supported fits are "glm", "gam", or NULL.
Classification uses rtemis.draw::draw_confusion() with stored confusion frequencies
when available, preserving the producer's class order. Otherwise it counts
aligned reference/predicted pairs. An omitted what selects test, validation,
then training for an ordinary classifier, or all available samples for a
resampled classifier. Multiple samples share one widget and one export.
Balanced accuracy in this view is macro recall, not the multiclass average
of one-versus-rest balanced accuracies. See
rtemis.draw::ConfusionConfig for zero-denominator and pooled-count semantics.