diff options
Diffstat (limited to 'python/pyspark/ml/param/__init__.py')
| -rw-r--r-- | python/pyspark/ml/param/__init__.py | 118 |
1 files changed, 84 insertions, 34 deletions
diff --git a/python/pyspark/ml/param/__init__.py b/python/pyspark/ml/param/__init__.py index 49c20b4cf7..67fb6e3dc7 100644 --- a/python/pyspark/ml/param/__init__.py +++ b/python/pyspark/ml/param/__init__.py @@ -16,6 +16,7 @@ # from abc import ABCMeta +import copy from pyspark.ml.util import Identifiable @@ -29,9 +30,9 @@ class Param(object): """ def __init__(self, parent, name, doc): - if not isinstance(parent, Params): - raise TypeError("Parent must be a Params but got type %s." % type(parent)) - self.parent = parent + if not isinstance(parent, Identifiable): + raise TypeError("Parent must be an Identifiable but got type %s." % type(parent)) + self.parent = parent.uid self.name = str(name) self.doc = str(doc) @@ -41,6 +42,15 @@ class Param(object): def __repr__(self): return "Param(parent=%r, name=%r, doc=%r)" % (self.parent, self.name, self.doc) + def __hash__(self): + return hash(str(self)) + + def __eq__(self, other): + if isinstance(other, Param): + return self.parent == other.parent and self.name == other.name + else: + return False + class Params(Identifiable): """ @@ -51,10 +61,13 @@ class Params(Identifiable): __metaclass__ = ABCMeta #: internal param map for user-supplied values param map - paramMap = {} + _paramMap = {} #: internal param map for default values - defaultParamMap = {} + _defaultParamMap = {} + + #: value returned by :py:func:`params` + _params = None @property def params(self): @@ -63,10 +76,12 @@ class Params(Identifiable): uses :py:func:`dir` to get all attributes of type :py:class:`Param`. """ - return list(filter(lambda attr: isinstance(attr, Param), - [getattr(self, x) for x in dir(self) if x != "params"])) + if self._params is None: + self._params = list(filter(lambda attr: isinstance(attr, Param), + [getattr(self, x) for x in dir(self) if x != "params"])) + return self._params - def _explain(self, param): + def explainParam(self, param): """ Explains a single param and returns its name, doc, and optional default value and user-supplied value in a string. @@ -74,10 +89,10 @@ class Params(Identifiable): param = self._resolveParam(param) values = [] if self.isDefined(param): - if param in self.defaultParamMap: - values.append("default: %s" % self.defaultParamMap[param]) - if param in self.paramMap: - values.append("current: %s" % self.paramMap[param]) + if param in self._defaultParamMap: + values.append("default: %s" % self._defaultParamMap[param]) + if param in self._paramMap: + values.append("current: %s" % self._paramMap[param]) else: values.append("undefined") valueStr = "(" + ", ".join(values) + ")" @@ -88,7 +103,7 @@ class Params(Identifiable): Returns the documentation of all params with their optionally default values and user-supplied values. """ - return "\n".join([self._explain(param) for param in self.params]) + return "\n".join([self.explainParam(param) for param in self.params]) def getParam(self, paramName): """ @@ -105,56 +120,76 @@ class Params(Identifiable): Checks whether a param is explicitly set by user. """ param = self._resolveParam(param) - return param in self.paramMap + return param in self._paramMap def hasDefault(self, param): """ Checks whether a param has a default value. """ param = self._resolveParam(param) - return param in self.defaultParamMap + return param in self._defaultParamMap def isDefined(self, param): """ - Checks whether a param is explicitly set by user or has a default value. + Checks whether a param is explicitly set by user or has + a default value. """ return self.isSet(param) or self.hasDefault(param) + def hasParam(self, paramName): + """ + Tests whether this instance contains a param with a given + (string) name. + """ + param = self._resolveParam(paramName) + return param in self.params + def getOrDefault(self, param): """ Gets the value of a param in the user-supplied param map or its default value. Raises an error if either is set. """ - if isinstance(param, Param): - if param in self.paramMap: - return self.paramMap[param] - else: - return self.defaultParamMap[param] - elif isinstance(param, str): - return self.getOrDefault(self.getParam(param)) + param = self._resolveParam(param) + if param in self._paramMap: + return self._paramMap[param] else: - raise KeyError("Cannot recognize %r as a param." % param) + return self._defaultParamMap[param] - def extractParamMap(self, extraParamMap={}): + def extractParamMap(self, extra={}): """ Extracts the embedded default param values and user-supplied values, and then merges them with extra values from input into a flat param map, where the latter value is used if there exist conflicts, i.e., with ordering: default param values < - user-supplied values < extraParamMap. - :param extraParamMap: extra param values + user-supplied values < extra. + :param extra: extra param values :return: merged param map """ - paramMap = self.defaultParamMap.copy() - paramMap.update(self.paramMap) - paramMap.update(extraParamMap) + paramMap = self._defaultParamMap.copy() + paramMap.update(self._paramMap) + paramMap.update(extra) return paramMap + def copy(self, extra={}): + """ + Creates a copy of this instance with the same uid and some + extra params. The default implementation creates a + shallow copy using :py:func:`copy.copy`, and then copies the + embedded and extra parameters over and returns the copy. + Subclasses should override this method if the default approach + is not sufficient. + :param extra: Extra parameters to copy to the new instance + :return: Copy of this instance + """ + that = copy.copy(self) + that._paramMap = self.extractParamMap(extra) + return that + def _shouldOwn(self, param): """ Validates that the input param belongs to this Params instance. """ - if param.parent is not self: + if not (self.uid == param.parent and self.hasParam(param.name)): raise ValueError("Param %r does not belong to %r." % (param, self)) def _resolveParam(self, param): @@ -175,7 +210,8 @@ class Params(Identifiable): @staticmethod def _dummy(): """ - Returns a dummy Params instance used as a placeholder to generate docs. + Returns a dummy Params instance used as a placeholder to + generate docs. """ dummy = Params() dummy.uid = "undefined" @@ -186,7 +222,7 @@ class Params(Identifiable): Sets user-supplied params. """ for param, value in kwargs.items(): - self.paramMap[getattr(self, param)] = value + self._paramMap[getattr(self, param)] = value return self def _setDefault(self, **kwargs): @@ -194,5 +230,19 @@ class Params(Identifiable): Sets default params. """ for param, value in kwargs.items(): - self.defaultParamMap[getattr(self, param)] = value + self._defaultParamMap[getattr(self, param)] = value return self + + def _copyValues(self, to, extra={}): + """ + Copies param values from this instance to another instance for + params shared by them. + :param to: the target instance + :param extra: extra params to be copied + :return: the target instance with param values copied + """ + paramMap = self.extractParamMap(extra) + for p in self.params: + if p in paramMap and to.hasParam(p.name): + to._set(**{p.name: paramMap[p]}) + return to |