diff --git a/NEWS.md b/NEWS.md index 934e229..50d629f 100644 --- a/NEWS.md +++ b/NEWS.md @@ -1,3 +1,104 @@ +# 0.105.0 # + +## Breaking changes + +None + +## New features + +* Added `Domain.n_features_in_` and `Domain.feature_names_in_` attributes. + +This brings domain decorators to conformance with "physical" Scikit-Learn input inspection standards such as [SLEP007](https://scikit-learn-enhancement-proposals.readthedocs.io/en/latest/slep007/proposal.html) and [SLEP010](https://scikit-learn-enhancement-proposals.readthedocs.io/en/latest/slep010/proposal.html). + +Domain decorators are natively about "logical" input inspection (ie. establishing and enforcing model's applicability domain). + +By combining these two complementary areas of functionality, they now make a great **first** step for any pipeline: + +``` python +from sklearn.datasets import load_iris +from sklearn.pipeline import Pipeline +from sklearn2pmml.decoration import ContinuousDomain + +iris_X, iris_y = load_iris(return_X_y = True, as_frame = True) + +pipeline = Pipeline([ + # Collect column-oriented model's applicability domain + ("domain", ContinuousDomain()), + ("classifier", ...) +]) +pipeline.fit(iris_X, iris_y) + +# Dynamic properties, delegate to (the attributes of-) the first step +print(pipeline.n_features_in_) +print(pipeline.feature_names_in_) +``` + +* Added `MultiDomain.n_features_in_` and `MultiDomain.feature_names_in_` attribute. + +* Added support for missing values in tree and tree ensemble models. + +Scikit-Learn 1.3 extended the `Tree` data structure with a `missing_go_to_left` field. +This field indicates the default split direction for each split, and is always present and populated whether the training dataset actually contained any missing values or not. + +As a result, Scikit-Learn 1.3 tree models are able to accept and make predictions on sparse datasets, even if they were trained on a fully dense dataset. +There is currently no mechanism for a data scientist to tag tree models as "can or cannot be used with missing values". + +The JPMML-SkLearn library implements two `Tree` data structure conversion modes, which can be toggled using the `allow_missing` conversion option. +The default mode corresponds to Scikit-Learn 0.18 through 1.2 behaviour, where a missing input causes the evaluation process to immediately bail out with a missing prediction. +The "missing allowed" mode corresponds to Scikit-Learn 1.3 and newer behaviour, where a missing input is ignored, and the evaluation proceeds to the pre-defined child branch until a final non-missing prediction is reached. + +Right now, the data scientist must activate the latter mode manually, by configuring `allow_missing = True`: + +``` python +from sklearn.tree import DecisionTreeClassifier +from sklearn2pmml.pipeline import PMMLPipeline + +pipeline = PMMLPipeline([ + ("classifier", DecisionTreeClassifier()) +]) +pipeline.fit(X, y) + +# Default mode +pipeline.configure(allow_missing = False) +sklearn2pmml(pipeline, "DecisionTree-default.pmml") + +# "Missing allowed" mode +pipeline.configure(allow_missing = True) +sklearn2pmml(pipeline, "DecisionTree-missing_allowed.pmml") +``` + +Both conversion modes generate standard PMML markup. +However, the "missing allowed" mode results in slightly bigger PMML documents (say, up to 10-15%), because the default split direction is encoded using extra `Node@defaultChild` and `Node@id` attributes. +The size difference disappears when the tree model is compacted. + +* Added support for nullable Pandas' scalar data types. + +If the dataset contains sparse columns, then they should be cast from the default Numpy `object` data type to the most appropriate nullable Pandas' scalar data type. The cast may be performed using a data type object (eg. `pandas.BooleanDtype`, `pandas.Int64Dtype`, `pandas.Float32Dtype`) or its string alias (eg. `Boolean`, `Int64`, `Float32`). + +This kind of "type hinting" is instrumental to generating high(er) quality PMML documents. + +## Minor improvements and fixes + +* Added `ExpressionRegressor.normalization_method` attribute. + +This attribute allows performing some most common normalizations atomically. + +The list of supported values is `none` and `exp`. + +* Refactored `ExpressionClassifier.normalization_method` attribute. + +The list of supported values is `none`, `logit`, `simplemax` and `softmax`. + +* Fixed the formatting of non-finite tree split values. + +It is possible that some tree splits perform comparisons against the positive infinity to indicate "always true" and "always false" conditions (eg. `x <= +Inf` and `x > +Inf`, respectively). + +Previously, infinite values were formatted using Java's default formatting method, which resulted in Java-style `-Infinity` and `Infinity` string literals. +They are now detected and replaced with PMML-style `-INF` and `INF` (case insensitive) string literals, respectively. + +* Ensured compatibility with CHAID 5.4.1. + + # 0.104.1 # ## Breaking changes @@ -335,10 +436,10 @@ It is there for information purposes only. Its presence or absence does not affe * Fixed the `Domain.transform(X)` method to preserve the `X` argument unchanged. -If the decorator needs to modify the dataset in any way (eg. performing missing or invalid value replacement), then it will create a copy of the argument dataset before modifying it. +If the domain decorator needs to modify the dataset in any way (eg. performing missing or invalid value replacement), then it will create a copy of the argument dataset before modifying it. Otherwise, the argument dataset is passed through as-is. -This aligns decorators with Scikit-Learn API guidelines that transformers and transformer-likes should not tamper with the original dataset. +This aligns domain decorators with Scikit-Learn API guidelines that transformers and transformer-likes should not tamper with the original dataset. * Added support for One-Model-Per-Target (OMPT)-style multi-target XGBoost estimators. @@ -401,7 +502,7 @@ See [SkLearn2PMML-402](https://github.com/jpmml/sklearn2pmml/issues/402) * Added support for multi-column mode to the `DiscreteDomain` class and its subclasses (`CategoricalDomain` and `OrdinalDomain`). -This brings discrete decorators to functional parity with continuous decorators, which have been supporting both single-column and multi-column mode for years. +This brings discrete domain decorators to functional parity with continuous domain decorators, which have been supporting both single-column and multi-column mode for years. Before: @@ -461,9 +562,9 @@ If the `CastTransformer.dtype` parameter value is "category" (ie. a string liter The subsequent transform method invocations are now guaranteed to exhibit stable transformation behaviour. Previously, each method call was computing its own set of valid category values. -* Added the `Decorator` class to the `sklearn.base.OneToOneFeatureMixin` class hierarchy. +* Added the `Domain` class to the `sklearn.base.OneToOneFeatureMixin` class hierarchy. -This makes decorators compatible with Scikit-Learn's `set_output` API. +This makes domain decorators compatible with Scikit-Learn's `set_output` API. Choosing a data container for transformation results: diff --git a/README.md b/README.md index 869a301..7400513 100644 --- a/README.md +++ b/README.md @@ -9,13 +9,13 @@ This package is a thin Python wrapper around the [JPMML-SkLearn](https://github. # News and Updates # -The current version is **0.104.1** (14 March, 2024): +The current version is **0.105.0** (21 March, 2024): ``` -pip install sklearn2pmml==0.104.1 +pip install sklearn2pmml==0.105.0 ``` -See the [NEWS.md](https://github.com/jpmml/sklearn2pmml/blob/master/NEWS.md#01041) file. +See the [NEWS.md](https://github.com/jpmml/sklearn2pmml/blob/master/NEWS.md#01050) file. # Prerequisites #