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sparksupport.py
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sparksupport.py
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Every record of this DataFrame contains the label and
# features represented by a vector.
df = sqlContext.createDataFrame(data, ["label", "features"])
# Set parameters for the algorithm.
# Here, we limit the number of iterations to 10.
lr = LogisticRegression(maxIter=10)
# Fit the model to the data.
model = lr.fit(df)
# Given a dataset, predict each point's label, and show the results.
model.transform(df).show()
import sys
import numpy as np
from pyspark.sql import SparkSession
def parseVector(line):
return np.array([float(x) for x in line.split(' ')])
def closestPoint(p, centers):
bestIndex = 0
closest = float("+inf")
for i in range(len(centers)):
tempDist = np.sum((p - centers[i]) ** 2)
if tempDist < closest:
closest = tempDist
bestIndex = i
return bestIndex
if __name__ == "__main__":
if len(sys.argv) != 4:
print("Usage: kmeans <file> <k> <convergeDist>", file=sys.stderr)
sys.exit(-1)
print("""WARN: This is a naive implementation of KMeans Clustering and is given
as an example! Please refer to examples/src/main/python/ml/kmeans_example.py for an
example on how to use ML's KMeans implementation.""", file=sys.stderr)
spark = SparkSession\
.builder\
.appName("PythonKMeans")\
.getOrCreate()
lines = spark.read.text(sys.argv[1]).rdd.map(lambda r: r[0])
data = lines.map(parseVector).cache()
K = int(sys.argv[2])
convergeDist = float(sys.argv[3])
kPoints = data.takeSample(False, K, 1)
tempDist = 1.0
while tempDist > convergeDist:
closest = data.map(
lambda p: (closestPoint(p, kPoints), (p, 1)))
pointStats = closest.reduceByKey(
lambda p1_c1, p2_c2: (p1_c1[0] + p2_c2[0], p1_c1[1] + p2_c2[1]))
newPoints = pointStats.map(
lambda st: (st[0], st[1][0] / st[1][1])).collect()
tempDist = sum(np.sum((kPoints[iK] - p) ** 2) for (iK, p) in newPoints)
for (iK, p) in newPoints:
kPoints[iK] = p
print("Final centers: " + str(kPoints))
spark.stop()