Object does not implement or subclass weka.classifiers.Classifier: __builtin__.list

[colingoldberg]

Hi,

As a weka novice, I ran a test of auto-weka using the weka python wrapper, getting this error. The test was run on an AWS EC2 Linux instance.

My python script is as follows:

import weka.core.packages as packages
from weka.classifiers import Classifier
from weka.core.converters import Loader
from weka.core.dataset import Instances
from weka.classifiers import Classifier
import weka.core.serialization as serialization
import weka.core.jvm as jvm

jvm.start()

loader = Loader("weka.core.converters.ArffLoader")
data = loader.load_file('./weather.arff')
data.class_is_last()
classifier = Classifier("weka.classifiers.meta.AutoWEKAClassifier",
["-seed", "123", "-timeLimit", "15", "-memLimit", "1024",
"-nBestConfigs", "1", "-metric", "errorRate", "-parallelRuns", "1"])
classifier.build_classifier(data)
outfile = './weather.model'
serialization.write_all(outfile, [classifier, Instances.template_instances(data)])

jvm.stop()
quit()

End of script

Both WEKA_JAR_PATH and CLASSPATH were explicitly exported.
export WEKA_JAR_PATH=/usr/local/share/weka/weka-3-8-1/weka.jar
export CLASSPATH=/usr/local/share/weka/weka-3-8-1/weka.jar

The Auto-Weka package was installed as follows:
java weka.core.WekaPackageManager -install-package Auto-WEKA

The traceback output was:
Traceback (most recent call last):
File "autoweka.py", line 16, in
"-nBestConfigs", "1", "-metric", "errorRate", "-parallelRuns", "1"])
File "/usr/local/lib/python2.7/site-packages/weka/classifiers.py", line 54, in init
self.enforce_type(jobject, "weka.classifiers.Classifier")
File "/usr/local/lib/python2.7/site-packages/weka/core/classes.py", line 573, in enforce_type
raise TypeError("Object does not implement or subclass " + intf_or_class + ": " + get_classname(jobject))
TypeError: Object does not implement or subclass weka.classifiers.Classifier: builtin.list

I bring this to your attention, not really knowing if I omitted something or if this is a bug.

Can you help?

Colin Goldberg

[larskotthoff]

This looks like a bug with the Python wrapper. I don't have any experience with this, sorry!