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Write or improve a Python function based on this description: Predict values for a single data point or an RDD of points using the model trained.
def predict(self, x): """ Predict values for a single data point or an RDD of points using the model trained. """ if isinstance(x, RDD): return x.map(lambda v: self.predict(v)) x = _convert_to_vector(x) margin = self.weights.dot(x) + self.intercept ...
Write or improve a Python function based on this description: Save this model to the given path.
def save(self, sc, path): """ Save this model to the given path. """ java_model = sc._jvm.org.apache.spark.mllib.classification.SVMModel( _py2java(sc, self._coeff), self.intercept) java_model.save(sc._jsc.sc(), path)
Write or improve a Python function based on this description: Load a model from the given path.
def load(cls, sc, path): """ Load a model from the given path. """ java_model = sc._jvm.org.apache.spark.mllib.classification.SVMModel.load( sc._jsc.sc(), path) weights = _java2py(sc, java_model.weights()) intercept = java_model.intercept() threshold =...
Write or improve a Python function based on this description: Train a Naive Bayes model given an RDD of (label, features) vectors. This is the Multinomial NB (U{http://tinyurl.com/lsdw6p}) which can handle all kinds of discrete data. For example, by converting documents into TF-IDF ve...
def train(cls, data, lambda_=1.0): """ Train a Naive Bayes model given an RDD of (label, features) vectors. This is the Multinomial NB (U{http://tinyurl.com/lsdw6p}) which can handle all kinds of discrete data. For example, by converting documents into TF-IDF vectors, i...
Write or improve a Python function based on this description: Push item onto heap, maintaining the heap invariant.
def heappush(heap, item): """Push item onto heap, maintaining the heap invariant.""" heap.append(item) _siftdown(heap, 0, len(heap)-1)
Write or improve a Python function based on this description: Pop the smallest item off the heap, maintaining the heap invariant.
def heappop(heap): """Pop the smallest item off the heap, maintaining the heap invariant.""" lastelt = heap.pop() # raises appropriate IndexError if heap is empty if heap: returnitem = heap[0] heap[0] = lastelt _siftup(heap, 0) return returnitem return lastelt
Write or improve a Python function based on this description: Pop and return the current smallest value, and add the new item. This is more efficient than heappop() followed by heappush(), and can be more appropriate when using a fixed-size heap. Note that the value returned may be larger than item! Tha...
def heapreplace(heap, item): """Pop and return the current smallest value, and add the new item. This is more efficient than heappop() followed by heappush(), and can be more appropriate when using a fixed-size heap. Note that the value returned may be larger than item! That constrains reasonable use...
Write or improve a Python function based on this description: Fast version of a heappush followed by a heappop.
def heappushpop(heap, item): """Fast version of a heappush followed by a heappop.""" if heap and heap[0] < item: item, heap[0] = heap[0], item _siftup(heap, 0) return item
Write or improve a Python function based on this description: Transform list into a heap, in-place, in O(len(x)) time.
def heapify(x): """Transform list into a heap, in-place, in O(len(x)) time.""" n = len(x) # Transform bottom-up. The largest index there's any point to looking at # is the largest with a child index in-range, so must have 2*i + 1 < n, # or i < (n-1)/2. If n is even = 2*j, this is (2*j-1)/2 = j-1/2...
Write or improve a Python function based on this description: Maxheap version of a heappop.
def _heappop_max(heap): """Maxheap version of a heappop.""" lastelt = heap.pop() # raises appropriate IndexError if heap is empty if heap: returnitem = heap[0] heap[0] = lastelt _siftup_max(heap, 0) return returnitem return lastelt
Write or improve a Python function based on this description: Maxheap version of a heappop followed by a heappush.
def _heapreplace_max(heap, item): """Maxheap version of a heappop followed by a heappush.""" returnitem = heap[0] # raises appropriate IndexError if heap is empty heap[0] = item _siftup_max(heap, 0) return returnitem
Write or improve a Python function based on this description: Transform list into a maxheap, in-place, in O(len(x)) time.
def _heapify_max(x): """Transform list into a maxheap, in-place, in O(len(x)) time.""" n = len(x) for i in reversed(range(n//2)): _siftup_max(x, i)
Write or improve a Python function based on this description: Maxheap variant of _siftdown
def _siftdown_max(heap, startpos, pos): 'Maxheap variant of _siftdown' newitem = heap[pos] # Follow the path to the root, moving parents down until finding a place # newitem fits. while pos > startpos: parentpos = (pos - 1) >> 1 parent = heap[parentpos] if parent < newitem: ...
Write or improve a Python function based on this description: Maxheap variant of _siftup
def _siftup_max(heap, pos): 'Maxheap variant of _siftup' endpos = len(heap) startpos = pos newitem = heap[pos] # Bubble up the larger child until hitting a leaf. childpos = 2*pos + 1 # leftmost child position while childpos < endpos: # Set childpos to index of larger child. ...
Write or improve a Python function based on this description: Merge multiple sorted inputs into a single sorted output. Similar to sorted(itertools.chain(*iterables)) but returns a generator, does not pull the data into memory all at once, and assumes that each of the input streams is already sorted (smal...
def merge(iterables, key=None, reverse=False): '''Merge multiple sorted inputs into a single sorted output. Similar to sorted(itertools.chain(*iterables)) but returns a generator, does not pull the data into memory all at once, and assumes that each of the input streams is already sorted (smallest to l...
Write or improve a Python function based on this description: Find the n smallest elements in a dataset. Equivalent to: sorted(iterable, key=key)[:n]
def nsmallest(n, iterable, key=None): """Find the n smallest elements in a dataset. Equivalent to: sorted(iterable, key=key)[:n] """ # Short-cut for n==1 is to use min() if n == 1: it = iter(iterable) sentinel = object() if key is None: result = min(it, default...
Write or improve a Python function based on this description: Find the n largest elements in a dataset. Equivalent to: sorted(iterable, key=key, reverse=True)[:n]
def nlargest(n, iterable, key=None): """Find the n largest elements in a dataset. Equivalent to: sorted(iterable, key=key, reverse=True)[:n] """ # Short-cut for n==1 is to use max() if n == 1: it = iter(iterable) sentinel = object() if key is None: result = max...
Write or improve a Python function based on this description: Compute the correlation matrix with specified method using dataset. :param dataset: A Dataset or a DataFrame. :param column: The name of the column of vectors for which the correlation coefficient needs to be c...
def corr(dataset, column, method="pearson"): """ Compute the correlation matrix with specified method using dataset. :param dataset: A Dataset or a DataFrame. :param column: The name of the column of vectors for which the correlation coefficient needs to be...
Write or improve a Python function based on this description: Given a list of metrics, provides a builder that it turns computes metrics from a column. See the documentation of [[Summarizer]] for an example. The following metrics are accepted (case sensitive): - mean: a vector that contains ...
def metrics(*metrics): """ Given a list of metrics, provides a builder that it turns computes metrics from a column. See the documentation of [[Summarizer]] for an example. The following metrics are accepted (case sensitive): - mean: a vector that contains the coefficient-wise...
Write or improve a Python function based on this description: Returns an aggregate object that contains the summary of the column with the requested metrics. :param featuresCol: a column that contains features Vector object. :param weightCol: a column that contains weight val...
def summary(self, featuresCol, weightCol=None): """ Returns an aggregate object that contains the summary of the column with the requested metrics. :param featuresCol: a column that contains features Vector object. :param weightCol: a column that contains weigh...
Write or improve a Python function based on this description: Compute the correlation (matrix) for the input RDD(s) using the specified method. Methods currently supported: I{pearson (default), spearman}. If a single RDD of Vectors is passed in, a correlation matrix comparing the colum...
def corr(x, y=None, method=None): """ Compute the correlation (matrix) for the input RDD(s) using the specified method. Methods currently supported: I{pearson (default), spearman}. If a single RDD of Vectors is passed in, a correlation matrix comparing the columns in the...
Write or improve a Python function based on this description: Creates a list of callables which can be called from different threads to fit and evaluate an estimator in parallel. Each callable returns an `(index, metric)` pair. :param est: Estimator, the estimator to be fit. :param train: DataFrame, train...
def _parallelFitTasks(est, train, eva, validation, epm, collectSubModel): """ Creates a list of callables which can be called from different threads to fit and evaluate an estimator in parallel. Each callable returns an `(index, metric)` pair. :param est: Estimator, the estimator to be fit. :param ...
Write or improve a Python function based on this description: Sets the given parameters in this grid to fixed values. Accepts either a parameter dictionary or a list of (parameter, value) pairs.
def baseOn(self, *args): """ Sets the given parameters in this grid to fixed values. Accepts either a parameter dictionary or a list of (parameter, value) pairs. """ if isinstance(args[0], dict): self.baseOn(*args[0].items()) else: for (param, valu...
Write or improve a Python function based on this description: Builds and returns all combinations of parameters specified by the param grid.
def build(self): """ Builds and returns all combinations of parameters specified by the param grid. """ keys = self._param_grid.keys() grid_values = self._param_grid.values() def to_key_value_pairs(keys, values): return [(key, key.typeConverter(value)...
Write or improve a Python function based on this description: Return Python estimator, estimatorParamMaps, and evaluator from a Java ValidatorParams.
def _from_java_impl(cls, java_stage): """ Return Python estimator, estimatorParamMaps, and evaluator from a Java ValidatorParams. """ # Load information from java_stage to the instance. estimator = JavaParams._from_java(java_stage.getEstimator()) evaluator = JavaParams._...
Write or improve a Python function based on this description: Return Java estimator, estimatorParamMaps, and evaluator from this Python instance.
def _to_java_impl(self): """ Return Java estimator, estimatorParamMaps, and evaluator from this Python instance. """ gateway = SparkContext._gateway cls = SparkContext._jvm.org.apache.spark.ml.param.ParamMap java_epms = gateway.new_array(cls, len(self.getEstimatorParamM...
Write or improve a Python function based on this description: Given a Java CrossValidator, create and return a Python wrapper of it. Used for ML persistence.
def _from_java(cls, java_stage): """ Given a Java CrossValidator, create and return a Python wrapper of it. Used for ML persistence. """ estimator, epms, evaluator = super(CrossValidator, cls)._from_java_impl(java_stage) numFolds = java_stage.getNumFolds() seed =...
Write or improve a Python function based on this description: Transfer this instance to a Java CrossValidator. Used for ML persistence. :return: Java object equivalent to this instance.
def _to_java(self): """ Transfer this instance to a Java CrossValidator. Used for ML persistence. :return: Java object equivalent to this instance. """ estimator, epms, evaluator = super(CrossValidator, self)._to_java_impl() _java_obj = JavaParams._new_java_obj("org.ap...
Write or improve a Python function based on this description: Creates a copy of this instance with a randomly generated uid and some extra params. This copies the underlying bestModel, creates a deep copy of the embedded paramMap, and copies the embedded and extra parameters over. It do...
def copy(self, extra=None): """ Creates a copy of this instance with a randomly generated uid and some extra params. This copies the underlying bestModel, creates a deep copy of the embedded paramMap, and copies the embedded and extra parameters over. It does not copy the...
Write or improve a Python function based on this description: setParams(self, estimator=None, estimatorParamMaps=None, evaluator=None, trainRatio=0.75,\ parallelism=1, collectSubModels=False, seed=None): Sets params for the train validation split.
def setParams(self, estimator=None, estimatorParamMaps=None, evaluator=None, trainRatio=0.75, parallelism=1, collectSubModels=False, seed=None): """ setParams(self, estimator=None, estimatorParamMaps=None, evaluator=None, trainRatio=0.75,\ parallelism=1, collectSubMod...
Write or improve a Python function based on this description: Creates a copy of this instance with a randomly generated uid and some extra params. This copies creates a deep copy of the embedded paramMap, and copies the embedded and extra parameters over. :param extra: Extra parameters to copy...
def copy(self, extra=None): """ Creates a copy of this instance with a randomly generated uid and some extra params. This copies creates a deep copy of the embedded paramMap, and copies the embedded and extra parameters over. :param extra: Extra parameters to copy to the new ins...
Write or improve a Python function based on this description: Given a Java TrainValidationSplit, create and return a Python wrapper of it. Used for ML persistence.
def _from_java(cls, java_stage): """ Given a Java TrainValidationSplit, create and return a Python wrapper of it. Used for ML persistence. """ estimator, epms, evaluator = super(TrainValidationSplit, cls)._from_java_impl(java_stage) trainRatio = java_stage.getTrainRatio(...
Write or improve a Python function based on this description: Transfer this instance to a Java TrainValidationSplit. Used for ML persistence. :return: Java object equivalent to this instance.
def _to_java(self): """ Transfer this instance to a Java TrainValidationSplit. Used for ML persistence. :return: Java object equivalent to this instance. """ estimator, epms, evaluator = super(TrainValidationSplit, self)._to_java_impl() _java_obj = JavaParams._new_java_...
Write or improve a Python function based on this description: Creates a copy of this instance with a randomly generated uid and some extra params. This copies the underlying bestModel, creates a deep copy of the embedded paramMap, and copies the embedded and extra parameters over. And, ...
def copy(self, extra=None): """ Creates a copy of this instance with a randomly generated uid and some extra params. This copies the underlying bestModel, creates a deep copy of the embedded paramMap, and copies the embedded and extra parameters over. And, this creates a ...
Write or improve a Python function based on this description: Given a Java TrainValidationSplitModel, create and return a Python wrapper of it. Used for ML persistence.
def _from_java(cls, java_stage): """ Given a Java TrainValidationSplitModel, create and return a Python wrapper of it. Used for ML persistence. """ # Load information from java_stage to the instance. bestModel = JavaParams._from_java(java_stage.bestModel()) estim...
Write or improve a Python function based on this description: Transfer this instance to a Java TrainValidationSplitModel. Used for ML persistence. :return: Java object equivalent to this instance.
def _to_java(self): """ Transfer this instance to a Java TrainValidationSplitModel. Used for ML persistence. :return: Java object equivalent to this instance. """ sc = SparkContext._active_spark_context # TODO: persst validation metrics as well _java_obj = JavaPa...
Write or improve a Python function based on this description: Returns the value of Spark runtime configuration property for the given key, assuming it is set.
def get(self, key, default=_NoValue): """Returns the value of Spark runtime configuration property for the given key, assuming it is set. """ self._checkType(key, "key") if default is _NoValue: return self._jconf.get(key) else: if default is not No...
Write or improve a Python function based on this description: Assert that an object is of type str.
def _checkType(self, obj, identifier): """Assert that an object is of type str.""" if not isinstance(obj, basestring): raise TypeError("expected %s '%s' to be a string (was '%s')" % (identifier, obj, type(obj).__name__))
Write or improve a Python function based on this description: Create a PySpark function by its name
def _create_function(name, doc=""): """Create a PySpark function by its name""" def _(col): sc = SparkContext._active_spark_context jc = getattr(sc._jvm.functions, name)(col._jc if isinstance(col, Column) else col) return Column(jc) _.__name__ = name _.__doc__ = doc return _
Write or improve a Python function based on this description: Similar with `_create_function` but creates a PySpark function that takes a column (as string as well). This is mainly for PySpark functions to take strings as column names.
def _create_function_over_column(name, doc=""): """Similar with `_create_function` but creates a PySpark function that takes a column (as string as well). This is mainly for PySpark functions to take strings as column names. """ def _(col): sc = SparkContext._active_spark_context jc ...
Write or improve a Python function based on this description: Wrap the deprecated function to print out deprecation warnings
def _wrap_deprecated_function(func, message): """ Wrap the deprecated function to print out deprecation warnings""" def _(col): warnings.warn(message, DeprecationWarning) return func(col) return functools.wraps(func)(_)
Write or improve a Python function based on this description: Create a binary mathfunction by name
def _create_binary_mathfunction(name, doc=""): """ Create a binary mathfunction by name""" def _(col1, col2): sc = SparkContext._active_spark_context # For legacy reasons, the arguments here can be implicitly converted into floats, # if they are not columns or strings. if isinsta...
Write or improve a Python function based on this description: Create a window function by name
def _create_window_function(name, doc=''): """ Create a window function by name """ def _(): sc = SparkContext._active_spark_context jc = getattr(sc._jvm.functions, name)() return Column(jc) _.__name__ = name _.__doc__ = 'Window function: ' + doc return _
Write or improve a Python function based on this description: Aggregate function: returns a new :class:`Column` for approximate distinct count of column `col`. :param rsd: maximum estimation error allowed (default = 0.05). For rsd < 0.01, it is more efficient to use :func:`countDistinct` >>> df.a...
def approx_count_distinct(col, rsd=None): """Aggregate function: returns a new :class:`Column` for approximate distinct count of column `col`. :param rsd: maximum estimation error allowed (default = 0.05). For rsd < 0.01, it is more efficient to use :func:`countDistinct` >>> df.agg(approx_coun...
Write or improve a Python function based on this description: Marks a DataFrame as small enough for use in broadcast joins.
def broadcast(df): """Marks a DataFrame as small enough for use in broadcast joins.""" sc = SparkContext._active_spark_context return DataFrame(sc._jvm.functions.broadcast(df._jdf), df.sql_ctx)
Write or improve a Python function based on this description: Returns a new :class:`Column` for distinct count of ``col`` or ``cols``. >>> df.agg(countDistinct(df.age, df.name).alias('c')).collect() [Row(c=2)] >>> df.agg(countDistinct("age", "name").alias('c')).collect() [Row(c=2)]
def countDistinct(col, *cols): """Returns a new :class:`Column` for distinct count of ``col`` or ``cols``. >>> df.agg(countDistinct(df.age, df.name).alias('c')).collect() [Row(c=2)] >>> df.agg(countDistinct("age", "name").alias('c')).collect() [Row(c=2)] """ sc = SparkContext._active_spark...
Write or improve a Python function based on this description: Aggregate function: returns the last value in a group. The function by default returns the last values it sees. It will return the last non-null value it sees when ignoreNulls is set to true. If all values are null, then null is returned. .. n...
def last(col, ignorenulls=False): """Aggregate function: returns the last value in a group. The function by default returns the last values it sees. It will return the last non-null value it sees when ignoreNulls is set to true. If all values are null, then null is returned. .. note:: The function is ...
Write or improve a Python function based on this description: Returns col1 if it is not NaN, or col2 if col1 is NaN. Both inputs should be floating point columns (:class:`DoubleType` or :class:`FloatType`). >>> df = spark.createDataFrame([(1.0, float('nan')), (float('nan'), 2.0)], ("a", "b")) >>> df.sele...
def nanvl(col1, col2): """Returns col1 if it is not NaN, or col2 if col1 is NaN. Both inputs should be floating point columns (:class:`DoubleType` or :class:`FloatType`). >>> df = spark.createDataFrame([(1.0, float('nan')), (float('nan'), 2.0)], ("a", "b")) >>> df.select(nanvl("a", "b").alias("r1"), n...
Write or improve a Python function based on this description: Generates a random column with independent and identically distributed (i.i.d.) samples from U[0.0, 1.0]. .. note:: The function is non-deterministic in general case. >>> df.withColumn('rand', rand(seed=42) * 3).collect() [Row(age=2, name=...
def rand(seed=None): """Generates a random column with independent and identically distributed (i.i.d.) samples from U[0.0, 1.0]. .. note:: The function is non-deterministic in general case. >>> df.withColumn('rand', rand(seed=42) * 3).collect() [Row(age=2, name=u'Alice', rand=2.4052597283576684),...
Write or improve a Python function based on this description: Round the given value to `scale` decimal places using HALF_UP rounding mode if `scale` >= 0 or at integral part when `scale` < 0. >>> spark.createDataFrame([(2.5,)], ['a']).select(round('a', 0).alias('r')).collect() [Row(r=3.0)]
def round(col, scale=0): """ Round the given value to `scale` decimal places using HALF_UP rounding mode if `scale` >= 0 or at integral part when `scale` < 0. >>> spark.createDataFrame([(2.5,)], ['a']).select(round('a', 0).alias('r')).collect() [Row(r=3.0)] """ sc = SparkContext._active_spa...
Write or improve a Python function based on this description: Shift the given value numBits left. >>> spark.createDataFrame([(21,)], ['a']).select(shiftLeft('a', 1).alias('r')).collect() [Row(r=42)]
def shiftLeft(col, numBits): """Shift the given value numBits left. >>> spark.createDataFrame([(21,)], ['a']).select(shiftLeft('a', 1).alias('r')).collect() [Row(r=42)] """ sc = SparkContext._active_spark_context return Column(sc._jvm.functions.shiftLeft(_to_java_column(col), numBits))
Write or improve a Python function based on this description: (Signed) shift the given value numBits right. >>> spark.createDataFrame([(42,)], ['a']).select(shiftRight('a', 1).alias('r')).collect() [Row(r=21)]
def shiftRight(col, numBits): """(Signed) shift the given value numBits right. >>> spark.createDataFrame([(42,)], ['a']).select(shiftRight('a', 1).alias('r')).collect() [Row(r=21)] """ sc = SparkContext._active_spark_context jc = sc._jvm.functions.shiftRight(_to_java_column(col), numBits) r...
Write or improve a Python function based on this description: Parses the expression string into the column that it represents >>> df.select(expr("length(name)")).collect() [Row(length(name)=5), Row(length(name)=3)]
def expr(str): """Parses the expression string into the column that it represents >>> df.select(expr("length(name)")).collect() [Row(length(name)=5), Row(length(name)=3)] """ sc = SparkContext._active_spark_context return Column(sc._jvm.functions.expr(str))
Write or improve a Python function based on this description: Evaluates a list of conditions and returns one of multiple possible result expressions. If :func:`Column.otherwise` is not invoked, None is returned for unmatched conditions. :param condition: a boolean :class:`Column` expression. :param value:...
def when(condition, value): """Evaluates a list of conditions and returns one of multiple possible result expressions. If :func:`Column.otherwise` is not invoked, None is returned for unmatched conditions. :param condition: a boolean :class:`Column` expression. :param value: a literal value, or a :clas...
Write or improve a Python function based on this description: Returns the first argument-based logarithm of the second argument. If there is only one argument, then this takes the natural logarithm of the argument. >>> df.select(log(10.0, df.age).alias('ten')).rdd.map(lambda l: str(l.ten)[:7]).collect() ...
def log(arg1, arg2=None): """Returns the first argument-based logarithm of the second argument. If there is only one argument, then this takes the natural logarithm of the argument. >>> df.select(log(10.0, df.age).alias('ten')).rdd.map(lambda l: str(l.ten)[:7]).collect() ['0.30102', '0.69897'] >>...
Write or improve a Python function based on this description: Convert a number in a string column from one base to another. >>> df = spark.createDataFrame([("010101",)], ['n']) >>> df.select(conv(df.n, 2, 16).alias('hex')).collect() [Row(hex=u'15')]
def conv(col, fromBase, toBase): """ Convert a number in a string column from one base to another. >>> df = spark.createDataFrame([("010101",)], ['n']) >>> df.select(conv(df.n, 2, 16).alias('hex')).collect() [Row(hex=u'15')] """ sc = SparkContext._active_spark_context return Column(sc._...
Write or improve a Python function based on this description: Window function: returns the value that is `offset` rows before the current row, and `defaultValue` if there is less than `offset` rows before the current row. For example, an `offset` of one will return the previous row at any given point in the wi...
def lag(col, offset=1, default=None): """ Window function: returns the value that is `offset` rows before the current row, and `defaultValue` if there is less than `offset` rows before the current row. For example, an `offset` of one will return the previous row at any given point in the window partitio...
Write or improve a Python function based on this description: Window function: returns the ntile group id (from 1 to `n` inclusive) in an ordered window partition. For example, if `n` is 4, the first quarter of the rows will get value 1, the second quarter will get 2, the third quarter will get 3, and the ...
def ntile(n): """ Window function: returns the ntile group id (from 1 to `n` inclusive) in an ordered window partition. For example, if `n` is 4, the first quarter of the rows will get value 1, the second quarter will get 2, the third quarter will get 3, and the last quarter will get 4. This is...
Write or improve a Python function based on this description: Converts a date/timestamp/string to a value of string in the format specified by the date format given by the second argument. A pattern could be for instance `dd.MM.yyyy` and could return a string like '18.03.1993'. All pattern letters of the ...
def date_format(date, format): """ Converts a date/timestamp/string to a value of string in the format specified by the date format given by the second argument. A pattern could be for instance `dd.MM.yyyy` and could return a string like '18.03.1993'. All pattern letters of the Java class `java.tim...
Write or improve a Python function based on this description: Returns the date that is `days` days after `start` >>> df = spark.createDataFrame([('2015-04-08',)], ['dt']) >>> df.select(date_add(df.dt, 1).alias('next_date')).collect() [Row(next_date=datetime.date(2015, 4, 9))]
def date_add(start, days): """ Returns the date that is `days` days after `start` >>> df = spark.createDataFrame([('2015-04-08',)], ['dt']) >>> df.select(date_add(df.dt, 1).alias('next_date')).collect() [Row(next_date=datetime.date(2015, 4, 9))] """ sc = SparkContext._active_spark_context ...
Write or improve a Python function based on this description: Returns the number of days from `start` to `end`. >>> df = spark.createDataFrame([('2015-04-08','2015-05-10')], ['d1', 'd2']) >>> df.select(datediff(df.d2, df.d1).alias('diff')).collect() [Row(diff=32)]
def datediff(end, start): """ Returns the number of days from `start` to `end`. >>> df = spark.createDataFrame([('2015-04-08','2015-05-10')], ['d1', 'd2']) >>> df.select(datediff(df.d2, df.d1).alias('diff')).collect() [Row(diff=32)] """ sc = SparkContext._active_spark_context return Col...
Write or improve a Python function based on this description: Returns the date that is `months` months after `start` >>> df = spark.createDataFrame([('2015-04-08',)], ['dt']) >>> df.select(add_months(df.dt, 1).alias('next_month')).collect() [Row(next_month=datetime.date(2015, 5, 8))]
def add_months(start, months): """ Returns the date that is `months` months after `start` >>> df = spark.createDataFrame([('2015-04-08',)], ['dt']) >>> df.select(add_months(df.dt, 1).alias('next_month')).collect() [Row(next_month=datetime.date(2015, 5, 8))] """ sc = SparkContext._active_spa...
Write or improve a Python function based on this description: Returns number of months between dates date1 and date2. If date1 is later than date2, then the result is positive. If date1 and date2 are on the same day of month, or both are the last day of month, returns an integer (time of day will be ignore...
def months_between(date1, date2, roundOff=True): """ Returns number of months between dates date1 and date2. If date1 is later than date2, then the result is positive. If date1 and date2 are on the same day of month, or both are the last day of month, returns an integer (time of day will be ignored)...
Write or improve a Python function based on this description: Converts a :class:`Column` of :class:`pyspark.sql.types.StringType` or :class:`pyspark.sql.types.TimestampType` into :class:`pyspark.sql.types.DateType` using the optionally specified format. Specify formats according to `DateTimeFormatter <http...
def to_date(col, format=None): """Converts a :class:`Column` of :class:`pyspark.sql.types.StringType` or :class:`pyspark.sql.types.TimestampType` into :class:`pyspark.sql.types.DateType` using the optionally specified format. Specify formats according to `DateTimeFormatter <https://docs.oracle.com/javas...
Write or improve a Python function based on this description: Returns timestamp truncated to the unit specified by the format. :param format: 'year', 'yyyy', 'yy', 'month', 'mon', 'mm', 'day', 'dd', 'hour', 'minute', 'second', 'week', 'quarter' >>> df = spark.createDataFrame([('1997-02-28 05:02:11',)...
def date_trunc(format, timestamp): """ Returns timestamp truncated to the unit specified by the format. :param format: 'year', 'yyyy', 'yy', 'month', 'mon', 'mm', 'day', 'dd', 'hour', 'minute', 'second', 'week', 'quarter' >>> df = spark.createDataFrame([('1997-02-28 05:02:11',)], ['t']) >>...
Write or improve a Python function based on this description: Returns the first date which is later than the value of the date column. Day of the week parameter is case insensitive, and accepts: "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun". >>> df = spark.createDataFrame([('2015-07-27',)], ['d']) ...
def next_day(date, dayOfWeek): """ Returns the first date which is later than the value of the date column. Day of the week parameter is case insensitive, and accepts: "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun". >>> df = spark.createDataFrame([('2015-07-27',)], ['d']) >>> df.select(ne...
Write or improve a Python function based on this description: Returns the last day of the month which the given date belongs to. >>> df = spark.createDataFrame([('1997-02-10',)], ['d']) >>> df.select(last_day(df.d).alias('date')).collect() [Row(date=datetime.date(1997, 2, 28))]
def last_day(date): """ Returns the last day of the month which the given date belongs to. >>> df = spark.createDataFrame([('1997-02-10',)], ['d']) >>> df.select(last_day(df.d).alias('date')).collect() [Row(date=datetime.date(1997, 2, 28))] """ sc = SparkContext._active_spark_context re...
Write or improve a Python function based on this description: Convert time string with given pattern ('yyyy-MM-dd HH:mm:ss', by default) to Unix time stamp (in seconds), using the default timezone and the default locale, return null if fail. if `timestamp` is None, then it returns current timestamp. ...
def unix_timestamp(timestamp=None, format='yyyy-MM-dd HH:mm:ss'): """ Convert time string with given pattern ('yyyy-MM-dd HH:mm:ss', by default) to Unix time stamp (in seconds), using the default timezone and the default locale, return null if fail. if `timestamp` is None, then it returns current t...
Write or improve a Python function based on this description: This is a common function for databases supporting TIMESTAMP WITHOUT TIMEZONE. This function takes a timestamp which is timezone-agnostic, and interprets it as a timestamp in UTC, and renders that timestamp as a timestamp in the given time zone. ...
def from_utc_timestamp(timestamp, tz): """ This is a common function for databases supporting TIMESTAMP WITHOUT TIMEZONE. This function takes a timestamp which is timezone-agnostic, and interprets it as a timestamp in UTC, and renders that timestamp as a timestamp in the given time zone. However, t...
Write or improve a Python function based on this description: Bucketize rows into one or more time windows given a timestamp specifying column. Window starts are inclusive but the window ends are exclusive, e.g. 12:05 will be in the window [12:05,12:10) but not in [12:00,12:05). Windows can support microsecond...
def window(timeColumn, windowDuration, slideDuration=None, startTime=None): """Bucketize rows into one or more time windows given a timestamp specifying column. Window starts are inclusive but the window ends are exclusive, e.g. 12:05 will be in the window [12:05,12:10) but not in [12:00,12:05). Windows can...
Write or improve a Python function based on this description: Calculates the hash code of given columns, and returns the result as an int column. >>> spark.createDataFrame([('ABC',)], ['a']).select(hash('a').alias('hash')).collect() [Row(hash=-757602832)]
def hash(*cols): """Calculates the hash code of given columns, and returns the result as an int column. >>> spark.createDataFrame([('ABC',)], ['a']).select(hash('a').alias('hash')).collect() [Row(hash=-757602832)] """ sc = SparkContext._active_spark_context jc = sc._jvm.functions.hash(_to_seq(s...
Write or improve a Python function based on this description: Concatenates multiple input string columns together into a single string column, using the given separator. >>> df = spark.createDataFrame([('abcd','123')], ['s', 'd']) >>> df.select(concat_ws('-', df.s, df.d).alias('s')).collect() [Row(s=u...
def concat_ws(sep, *cols): """ Concatenates multiple input string columns together into a single string column, using the given separator. >>> df = spark.createDataFrame([('abcd','123')], ['s', 'd']) >>> df.select(concat_ws('-', df.s, df.d).alias('s')).collect() [Row(s=u'abcd-123')] """ ...
Write or improve a Python function based on this description: Computes the first argument into a string from a binary using the provided character set (one of 'US-ASCII', 'ISO-8859-1', 'UTF-8', 'UTF-16BE', 'UTF-16LE', 'UTF-16').
def decode(col, charset): """ Computes the first argument into a string from a binary using the provided character set (one of 'US-ASCII', 'ISO-8859-1', 'UTF-8', 'UTF-16BE', 'UTF-16LE', 'UTF-16'). """ sc = SparkContext._active_spark_context return Column(sc._jvm.functions.decode(_to_java_column(...
Write or improve a Python function based on this description: Formats the number X to a format like '#,--#,--#.--', rounded to d decimal places with HALF_EVEN round mode, and returns the result as a string. :param col: the column name of the numeric value to be formatted :param d: the N decimal places ...
def format_number(col, d): """ Formats the number X to a format like '#,--#,--#.--', rounded to d decimal places with HALF_EVEN round mode, and returns the result as a string. :param col: the column name of the numeric value to be formatted :param d: the N decimal places >>> spark.createDataFr...
Write or improve a Python function based on this description: Formats the arguments in printf-style and returns the result as a string column. :param col: the column name of the numeric value to be formatted :param d: the N decimal places >>> df = spark.createDataFrame([(5, "hello")], ['a', 'b']) >>>...
def format_string(format, *cols): """ Formats the arguments in printf-style and returns the result as a string column. :param col: the column name of the numeric value to be formatted :param d: the N decimal places >>> df = spark.createDataFrame([(5, "hello")], ['a', 'b']) >>> df.select(format...
Write or improve a Python function based on this description: Locate the position of the first occurrence of substr column in the given string. Returns null if either of the arguments are null. .. note:: The position is not zero based, but 1 based index. Returns 0 if substr could not be found in str. ...
def instr(str, substr): """ Locate the position of the first occurrence of substr column in the given string. Returns null if either of the arguments are null. .. note:: The position is not zero based, but 1 based index. Returns 0 if substr could not be found in str. >>> df = spark.createD...
Write or improve a Python function based on this description: Returns the substring from string str before count occurrences of the delimiter delim. If count is positive, everything the left of the final delimiter (counting from left) is returned. If count is negative, every to the right of the final delimiter...
def substring_index(str, delim, count): """ Returns the substring from string str before count occurrences of the delimiter delim. If count is positive, everything the left of the final delimiter (counting from left) is returned. If count is negative, every to the right of the final delimiter (counting ...
Write or improve a Python function based on this description: Computes the Levenshtein distance of the two given strings. >>> df0 = spark.createDataFrame([('kitten', 'sitting',)], ['l', 'r']) >>> df0.select(levenshtein('l', 'r').alias('d')).collect() [Row(d=3)]
def levenshtein(left, right): """Computes the Levenshtein distance of the two given strings. >>> df0 = spark.createDataFrame([('kitten', 'sitting',)], ['l', 'r']) >>> df0.select(levenshtein('l', 'r').alias('d')).collect() [Row(d=3)] """ sc = SparkContext._active_spark_context jc = sc._jvm.f...
Write or improve a Python function based on this description: Locate the position of the first occurrence of substr in a string column, after position pos. .. note:: The position is not zero based, but 1 based index. Returns 0 if substr could not be found in str. :param substr: a string :param st...
def locate(substr, str, pos=1): """ Locate the position of the first occurrence of substr in a string column, after position pos. .. note:: The position is not zero based, but 1 based index. Returns 0 if substr could not be found in str. :param substr: a string :param str: a Column of :cla...
Write or improve a Python function based on this description: Left-pad the string column to width `len` with `pad`. >>> df = spark.createDataFrame([('abcd',)], ['s',]) >>> df.select(lpad(df.s, 6, '#').alias('s')).collect() [Row(s=u'##abcd')]
def lpad(col, len, pad): """ Left-pad the string column to width `len` with `pad`. >>> df = spark.createDataFrame([('abcd',)], ['s',]) >>> df.select(lpad(df.s, 6, '#').alias('s')).collect() [Row(s=u'##abcd')] """ sc = SparkContext._active_spark_context return Column(sc._jvm.functions.lp...
Write or improve a Python function based on this description: Repeats a string column n times, and returns it as a new string column. >>> df = spark.createDataFrame([('ab',)], ['s',]) >>> df.select(repeat(df.s, 3).alias('s')).collect() [Row(s=u'ababab')]
def repeat(col, n): """ Repeats a string column n times, and returns it as a new string column. >>> df = spark.createDataFrame([('ab',)], ['s',]) >>> df.select(repeat(df.s, 3).alias('s')).collect() [Row(s=u'ababab')] """ sc = SparkContext._active_spark_context return Column(sc._jvm.func...
Write or improve a Python function based on this description: Splits str around matches of the given pattern. :param str: a string expression to split :param pattern: a string representing a regular expression. The regex string should be a Java regular expression. :param limit: an integer which co...
def split(str, pattern, limit=-1): """ Splits str around matches of the given pattern. :param str: a string expression to split :param pattern: a string representing a regular expression. The regex string should be a Java regular expression. :param limit: an integer which controls the numbe...
Write or improve a Python function based on this description: r"""Extract a specific group matched by a Java regex, from the specified string column. If the regex did not match, or the specified group did not match, an empty string is returned. >>> df = spark.createDataFrame([('100-200',)], ['str']) >>> d...
def regexp_extract(str, pattern, idx): r"""Extract a specific group matched by a Java regex, from the specified string column. If the regex did not match, or the specified group did not match, an empty string is returned. >>> df = spark.createDataFrame([('100-200',)], ['str']) >>> df.select(regexp_extr...
Write or improve a Python function based on this description: r"""Replace all substrings of the specified string value that match regexp with rep. >>> df = spark.createDataFrame([('100-200',)], ['str']) >>> df.select(regexp_replace('str', r'(\d+)', '--').alias('d')).collect() [Row(d=u'-----')]
def regexp_replace(str, pattern, replacement): r"""Replace all substrings of the specified string value that match regexp with rep. >>> df = spark.createDataFrame([('100-200',)], ['str']) >>> df.select(regexp_replace('str', r'(\d+)', '--').alias('d')).collect() [Row(d=u'-----')] """ sc = SparkC...
Write or improve a Python function based on this description: A function translate any character in the `srcCol` by a character in `matching`. The characters in `replace` is corresponding to the characters in `matching`. The translate will happen when any character in the string matching with the character ...
def translate(srcCol, matching, replace): """A function translate any character in the `srcCol` by a character in `matching`. The characters in `replace` is corresponding to the characters in `matching`. The translate will happen when any character in the string matching with the character in the `match...
Write or improve a Python function based on this description: Collection function: returns true if the arrays contain any common non-null element; if not, returns null if both the arrays are non-empty and any of them contains a null element; returns false otherwise. >>> df = spark.createDataFrame([(["a", ...
def arrays_overlap(a1, a2): """ Collection function: returns true if the arrays contain any common non-null element; if not, returns null if both the arrays are non-empty and any of them contains a null element; returns false otherwise. >>> df = spark.createDataFrame([(["a", "b"], ["b", "c"]), (["a...
Write or improve a Python function based on this description: Collection function: returns an array containing all the elements in `x` from index `start` (or starting from the end if `start` is negative) with the specified `length`. >>> df = spark.createDataFrame([([1, 2, 3],), ([4, 5],)], ['x']) >>> df.s...
def slice(x, start, length): """ Collection function: returns an array containing all the elements in `x` from index `start` (or starting from the end if `start` is negative) with the specified `length`. >>> df = spark.createDataFrame([([1, 2, 3],), ([4, 5],)], ['x']) >>> df.select(slice(df.x, 2, 2...
Write or improve a Python function based on this description: Concatenates the elements of `column` using the `delimiter`. Null values are replaced with `null_replacement` if set, otherwise they are ignored. >>> df = spark.createDataFrame([(["a", "b", "c"],), (["a", None],)], ['data']) >>> df.select(array...
def array_join(col, delimiter, null_replacement=None): """ Concatenates the elements of `column` using the `delimiter`. Null values are replaced with `null_replacement` if set, otherwise they are ignored. >>> df = spark.createDataFrame([(["a", "b", "c"],), (["a", None],)], ['data']) >>> df.select(a...
Write or improve a Python function based on this description: Concatenates multiple input columns together into a single column. The function works with strings, binary and compatible array columns. >>> df = spark.createDataFrame([('abcd','123')], ['s', 'd']) >>> df.select(concat(df.s, df.d).alias('s')).c...
def concat(*cols): """ Concatenates multiple input columns together into a single column. The function works with strings, binary and compatible array columns. >>> df = spark.createDataFrame([('abcd','123')], ['s', 'd']) >>> df.select(concat(df.s, df.d).alias('s')).collect() [Row(s=u'abcd123')]...
Write or improve a Python function based on this description: Collection function: Locates the position of the first occurrence of the given value in the given array. Returns null if either of the arguments are null. .. note:: The position is not zero based, but 1 based index. Returns 0 if the given v...
def array_position(col, value): """ Collection function: Locates the position of the first occurrence of the given value in the given array. Returns null if either of the arguments are null. .. note:: The position is not zero based, but 1 based index. Returns 0 if the given value could not be f...
Write or improve a Python function based on this description: Collection function: Returns element of array at given index in extraction if col is array. Returns value for the given key in extraction if col is map. :param col: name of column containing array or map :param extraction: index to check for in...
def element_at(col, extraction): """ Collection function: Returns element of array at given index in extraction if col is array. Returns value for the given key in extraction if col is map. :param col: name of column containing array or map :param extraction: index to check for in array or key to c...
Write or improve a Python function based on this description: Collection function: Remove all elements that equal to element from the given array. :param col: name of column containing array :param element: element to be removed from the array >>> df = spark.createDataFrame([([1, 2, 3, 1, 1],), ([],)], [...
def array_remove(col, element): """ Collection function: Remove all elements that equal to element from the given array. :param col: name of column containing array :param element: element to be removed from the array >>> df = spark.createDataFrame([([1, 2, 3, 1, 1],), ([],)], ['data']) >>> df...
Write or improve a Python function based on this description: Returns a new row for each element in the given array or map. Uses the default column name `col` for elements in the array and `key` and `value` for elements in the map unless specified otherwise. >>> from pyspark.sql import Row >>> eDF = s...
def explode(col): """ Returns a new row for each element in the given array or map. Uses the default column name `col` for elements in the array and `key` and `value` for elements in the map unless specified otherwise. >>> from pyspark.sql import Row >>> eDF = spark.createDataFrame([Row(a=1, in...
Write or improve a Python function based on this description: Extracts json object from a json string based on json path specified, and returns json string of the extracted json object. It will return null if the input json string is invalid. :param col: string column in json format :param path: path to t...
def get_json_object(col, path): """ Extracts json object from a json string based on json path specified, and returns json string of the extracted json object. It will return null if the input json string is invalid. :param col: string column in json format :param path: path to the json object to e...
Write or improve a Python function based on this description: Creates a new row for a json column according to the given field names. :param col: string column in json format :param fields: list of fields to extract >>> data = [("1", '''{"f1": "value1", "f2": "value2"}'''), ("2", '''{"f1": "value12"}''')...
def json_tuple(col, *fields): """Creates a new row for a json column according to the given field names. :param col: string column in json format :param fields: list of fields to extract >>> data = [("1", '''{"f1": "value1", "f2": "value2"}'''), ("2", '''{"f1": "value12"}''')] >>> df = spark.creat...
Write or improve a Python function based on this description: Parses a JSON string and infers its schema in DDL format. :param json: a JSON string or a string literal containing a JSON string. :param options: options to control parsing. accepts the same options as the JSON datasource .. versionchanged:: ...
def schema_of_json(json, options={}): """ Parses a JSON string and infers its schema in DDL format. :param json: a JSON string or a string literal containing a JSON string. :param options: options to control parsing. accepts the same options as the JSON datasource .. versionchanged:: 3.0 It...
Write or improve a Python function based on this description: Parses a CSV string and infers its schema in DDL format. :param col: a CSV string or a string literal containing a CSV string. :param options: options to control parsing. accepts the same options as the CSV datasource >>> df = spark.range(1) ...
def schema_of_csv(csv, options={}): """ Parses a CSV string and infers its schema in DDL format. :param col: a CSV string or a string literal containing a CSV string. :param options: options to control parsing. accepts the same options as the CSV datasource >>> df = spark.range(1) >>> df.selec...
Write or improve a Python function based on this description: Converts a column containing a :class:`StructType` into a CSV string. Throws an exception, in the case of an unsupported type. :param col: name of column containing a struct. :param options: options to control converting. accepts the same optio...
def to_csv(col, options={}): """ Converts a column containing a :class:`StructType` into a CSV string. Throws an exception, in the case of an unsupported type. :param col: name of column containing a struct. :param options: options to control converting. accepts the same options as the CSV datasour...
Write or improve a Python function based on this description: Collection function: returns the length of the array or map stored in the column. :param col: name of column or expression >>> df = spark.createDataFrame([([1, 2, 3],),([1],),([],)], ['data']) >>> df.select(size(df.data)).collect() [Row(si...
def size(col): """ Collection function: returns the length of the array or map stored in the column. :param col: name of column or expression >>> df = spark.createDataFrame([([1, 2, 3],),([1],),([],)], ['data']) >>> df.select(size(df.data)).collect() [Row(size(data)=3), Row(size(data)=1), Row(...
Write or improve a Python function based on this description: Collection function: sorts the input array in ascending or descending order according to the natural ordering of the array elements. Null elements will be placed at the beginning of the returned array in ascending order or at the end of the returned...
def sort_array(col, asc=True): """ Collection function: sorts the input array in ascending or descending order according to the natural ordering of the array elements. Null elements will be placed at the beginning of the returned array in ascending order or at the end of the returned array in descending...