diff options
Diffstat (limited to 'python/examples')
-rwxr-xr-x | python/examples/kmeans.py | 11 | ||||
-rwxr-xr-x | python/examples/logistic_regression.py | 8 | ||||
-rwxr-xr-x | python/examples/mllib/kmeans.py | 44 | ||||
-rwxr-xr-x | python/examples/mllib/logistic_regression.py | 50 |
4 files changed, 107 insertions, 6 deletions
diff --git a/python/examples/kmeans.py b/python/examples/kmeans.py index ba31af92fc..d8387b0b18 100755 --- a/python/examples/kmeans.py +++ b/python/examples/kmeans.py @@ -16,8 +16,13 @@ # """ -This example requires numpy (http://www.numpy.org/) +The K-means algorithm written from scratch against PySpark. In practice, +one may prefer to use the KMeans algorithm in MLlib, as shown in +python/examples/mllib/kmeans.py. + +This example requires NumPy (http://www.numpy.org/). """ + import sys import numpy as np @@ -49,9 +54,7 @@ if __name__ == "__main__": K = int(sys.argv[3]) convergeDist = float(sys.argv[4]) - # TODO: change this after we port takeSample() - #kPoints = data.takeSample(False, K, 34) - kPoints = data.take(K) + kPoints = data.takeSample(False, K, 1) tempDist = 1.0 while tempDist > convergeDist: diff --git a/python/examples/logistic_regression.py b/python/examples/logistic_regression.py index 1117dea538..28d52e6a40 100755 --- a/python/examples/logistic_regression.py +++ b/python/examples/logistic_regression.py @@ -16,9 +16,13 @@ # """ -A logistic regression implementation that uses NumPy (http://www.numpy.org) to act on batches -of input data using efficient matrix operations. +A logistic regression implementation that uses NumPy (http://www.numpy.org) +to act on batches of input data using efficient matrix operations. + +In practice, one may prefer to use the LogisticRegression algorithm in +MLlib, as shown in python/examples/mllib/logistic_regression.py. """ + from collections import namedtuple from math import exp from os.path import realpath diff --git a/python/examples/mllib/kmeans.py b/python/examples/mllib/kmeans.py new file mode 100755 index 0000000000..dec82ff34f --- /dev/null +++ b/python/examples/mllib/kmeans.py @@ -0,0 +1,44 @@ +# +# Licensed to the Apache Software Foundation (ASF) under one or more +# contributor license agreements. See the NOTICE file distributed with +# this work for additional information regarding copyright ownership. +# The ASF licenses this file to You under the Apache License, Version 2.0 +# (the "License"); you may not use this file except in compliance with +# the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +""" +A K-means clustering program using MLlib. + +This example requires NumPy (http://www.numpy.org/). +""" + +import sys + +import numpy as np +from pyspark import SparkContext +from pyspark.mllib.clustering import KMeans + + +def parseVector(line): + return np.array([float(x) for x in line.split(' ')]) + + +if __name__ == "__main__": + if len(sys.argv) < 4: + print >> sys.stderr, "Usage: kmeans <master> <file> <k>" + exit(-1) + sc = SparkContext(sys.argv[1], "KMeans") + lines = sc.textFile(sys.argv[2]) + data = lines.map(parseVector) + k = int(sys.argv[3]) + model = KMeans.train(data, k) + print "Final centers: " + str(model.clusterCenters) diff --git a/python/examples/mllib/logistic_regression.py b/python/examples/mllib/logistic_regression.py new file mode 100755 index 0000000000..8631051d00 --- /dev/null +++ b/python/examples/mllib/logistic_regression.py @@ -0,0 +1,50 @@ +# +# Licensed to the Apache Software Foundation (ASF) under one or more +# contributor license agreements. See the NOTICE file distributed with +# this work for additional information regarding copyright ownership. +# The ASF licenses this file to You under the Apache License, Version 2.0 +# (the "License"); you may not use this file except in compliance with +# the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +""" +Logistic regression using MLlib. + +This example requires NumPy (http://www.numpy.org/). +""" + +from math import exp +import sys + +import numpy as np +from pyspark import SparkContext +from pyspark.mllib.regression import LabeledPoint +from pyspark.mllib.classification import LogisticRegressionWithSGD + + +# Parse a line of text into an MLlib LabeledPoint object +def parsePoint(line): + values = [float(s) for s in line.split(' ')] + if values[0] == -1: # Convert -1 labels to 0 for MLlib + values[0] = 0 + return LabeledPoint(values[0], values[1:]) + + +if __name__ == "__main__": + if len(sys.argv) != 4: + print >> sys.stderr, "Usage: logistic_regression <master> <file> <iters>" + exit(-1) + sc = SparkContext(sys.argv[1], "PythonLR") + points = sc.textFile(sys.argv[2]).map(parsePoint) + iterations = int(sys.argv[3]) + model = LogisticRegressionWithSGD.train(points, iterations) + print "Final weights: " + str(model.weights) + print "Final intercept: " + str(model.intercept) |