mlr3 0.1.8

• Added S3 methods to combine ResampleResults and BenchmarkResults with
  c().
• Fixed a bug where automatic generation of row ids could lead to duplicated ids
  via Task$predict_newdata()/Task$rbind() (#423).

mlr3 0.1.7

• Switched to new roxygen2 documentation format for R6 classes.

• resample() and benchmark() now support progress bars via the package
  progressr.

• Row ids now must be numeric. It was previously allowed to have character row
  ids, but this lead to confusion and unnecessary code bloat. Row identifiers
  (e.g., to be used in plots) can still be part of the task, with row role
  "name".

• Row names can now be queried with Task$row_names.

• DataBackendMatrix now supports to store an optional (numeric) dense part.

• Added new method $filter() to filter ResampleResults to a subset of
  iterations.

• Removed deprecated character() -> object converters.

• Empty test sets are now handled separately by learners (#421). An empty
  prediction object is returned for all learners.

• The internal train and predict function of Learner now should be implemented
  as private method: instead of public methods train_internal and
  predict_internal, private methods .train and .predict are now
  encouraged.

• It is now encouraged to move some internal methods from public to private:

  • Learner$train_internal should now be private method $.train.
  • Learner$predict_internal should now be private method $.predict.
  • Measure$score_internal should now be private method $.score.
    The public methods will be deprecated in a future release.

• Removed arguments from the constructor of measures classif.debug and
  classif.costs. These can be set directly by msr().

mlr3 0.1.6

• We have published an article about mlr3 in the Journal of Open Source
  Software: https://joss.theoj.org/papers/10.21105/joss.01903.
  See citation("mlr3") for the citation info.
• New method Learner$reset().
• New method BenchmarkResult$filter().
• Learners returned by BenchmarkResult$learners are reset to encourage the
  safer alternative BenchmarkResult$score() to access trained models.
• Fix ordering of levels in PredictionClassif$set_threshold() (triggered an
  assertion).

mlr3 0.1.5

• Switched from package Metrics to package mlr3measures.
• Measures can now calculate all scores using micro or macro averaging (#400).
• Measures can now be configured to return a customizable performance score
  (instead of NA) in case the score cannot be calculated.
• Character columns are now treated differently from factor columns.
  In the long term, character() columns are supposed to store text.
• Fixed a bug triggered by integer grouping variables in Task (#396).
• benchmark_grid() now accepts instantiated resamplings under certain
  conditions.

mlr3 0.1.4

• Task$set_col_roles() and Task$set_row_roles() are now deprecated.
  Instead it is recommended for now to work with the lists Task$col_roles and
  Task$row_roles directly.
• Learner$predict_newdata() now works without argument task if the learner
  has been fitted with Learner$train() (#375).
• Names of column roles have been unified ("weights", "label",
  "stratify" and "groups" have been renamed).
• Replaced MeasureClassifF1 with MeasureClassifFScore and fixed a bug in the
  F1 performance calculation (#353). Thanks to @001ben for reporting.
• Stratification is now controlled via a task column role (was a parameter of
  class Resampling before).
• Added a S3 predict() method for class Learner to increase
  interoperability with other packages.
• Many objects now come with a $help() which opens the respective manual page.

mlr3 0.1.3

• It is now possible to predict and score results on the training set or on both
  training and test set.
  Learners can be instructed to predict on multiple sets by setting
  predict_sets (default: "test"). Measures operate on all sets specified in
  their field predict_sets (default: "test".

• ResampleResult$prediction and ResampleResult$predictions() are now methods
  instead of fields, and allow to extract predictions for different predict
  sets.

• ResampleResult$performance() has been renamed to ResampleResult$score()
  for consistency.

• BenchmarkResult$performance() has been renamed to BenchmarkResult$score()
  for consistency.

• Changed API for (internal) constructors accepting paradox::ParamSet().
  Instead of passing the initial values separately, the initial values must now
  be set directly in the ParamSet.

mlr3 0.1.2

• Deprecated support of automatically creating objects from strings.
  Instead, mlr3 provides the following helper functions intended to ease the
  creation of objects stored in dictionaries:
  tsk(), tgen(), lrn(), rsmp(), msr().

• BenchmarkResult now ensures that the stored ResampleResults are in a
  persistent order. Thus, ResampleResults can now be addressed by their
  position instead of their hash.

• New field BenchmarkResult$n_resample_results.

• New field BenchmarkResult$hashes.

• New method Task$rename().

• New S3 generic as_benchmark_result().

• Renamed Generator to TaskGenerator.

• Removed the control object mlr_control().

• Removed ResampleResult$combine().

• Removed BenchmarkResult$best().

mlr3 0.1.1

Initial upload to CRAN.