This code is not working:
================
from pyspark.ml.evaluation import RegressionEvaluator
from pyspark.ml.recommendation import ALS, ALSModel
from pyspark.sql import Row
als = ALS(maxIter=10, regParam=0.01, userCol="user_id", itemCol="movie_id",
ratingCol="rating")
model = als.fit(training)
model.save("/models/als")
model2 = ALSModel.load("/models/als") # <-- error here
=================
Gives rise to this error:
=================
---------------------------------------------------------------------------Py4JJavaError
Traceback (most recent call
last)<ipython-input-24-c0454f47bb1d> in <module>()----> 1 m2 =
ALSModel.load("/models/als")
/usr/local/spark/python/pyspark/ml/util.py in load(cls, path) 251
def load(cls, path): 252 """Reads an ML instance from the
input path, a shortcut of `read().load(path)`."""--> 253
return cls.read().load(path) 254 255
/usr/local/spark/python/pyspark/ml/util.py in load(self, path) 192
if not isinstance(path, basestring): 193 raise
TypeError("path should be a basestring, got type %s" % type(path))-->
194 java_obj = self._jread.load(path) 195 if not
hasattr(self._clazz, "_from_java"): 196 raise
NotImplementedError("This Java ML type cannot be loaded into Python
currently: %r"
/usr/local/spark/python/lib/py4j-0.10.4-src.zip/py4j/java_gateway.py
in __call__(self, *args) 1131 answer =
self.gateway_client.send_command(command) 1132 return_value
= get_return_value(-> 1133 answer, self.gateway_client,
self.target_id, self.name) 1134 1135 for temp_arg in
temp_args:
/usr/local/spark/python/pyspark/sql/utils.py in deco(*a, **kw) 61
def deco(*a, **kw): 62 try:---> 63 return
f(*a, **kw) 64 except py4j.protocol.Py4JJavaError as e:
65 s = e.java_exception.toString()
/usr/local/spark/python/lib/py4j-0.10.4-src.zip/py4j/protocol.py in
get_return_value(answer, gateway_client, target_id, name) 317
raise Py4JJavaError( 318 "An error
occurred while calling {0}{1}{2}.\n".--> 319
format(target_id, ".", name), value) 320 else: 321
raise Py4JError(
Py4JJavaError: An error occurred while calling o337.load.
: java.lang.UnsupportedOperationException: empty collection
at org.apache.spark.rdd.RDD$$anonfun$first$1.apply(RDD.scala:1370)
at
org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:151)
at
org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:112)
at org.apache.spark.rdd.RDD.withScope(RDD.scala:362)
at org.apache.spark.rdd.RDD.first(RDD.scala:1367)
at
org.apache.spark.ml.util.DefaultParamsReader$.loadMetadata(ReadWrite.scala:379)
at
org.apache.spark.ml.recommendation.ALSModel$ALSModelReader.load(ALS.scala:317)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
at py4j.Gateway.invoke(Gateway.java:280)
at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
at py4j.commands.CallCommand.execute(CallCommand.java:79)
at py4j.GatewayConnection.run(GatewayConnection.java:214)
at java.lang.Thread.run(Thread.java:748)
=================
