ValueError：未知的url类型：sklearn中的0.0错误

Question

I have a simple script that tries to convert a csv data file into a form that the tool svm_light can accept. Here's the code:

    import csv
import sys
import numpy as np
from sklearn.cross_validation import train_test_split

def svm_light_conversion(row):
    conv_row = row[len(row) - 1] + ' '

    for i in xrange(len(row) - 1):
        conv_row = conv_row + str(i + 1) + ':' + str(row[i]) + ' '

    return conv_row

def reaData(inputfile):

    with open(inputfile, 'r') as inFile: 
        reader = csv.reader(inFile)
        my_content = list(reader)

    my_content = my_content[0:len(my_content) - 1]

    return my_content

def converToSVMLiteFormat(outputfile, train, test):

    train_file = outputfile + '_train.dat'
    test_file = outputfile + '_test.dat'
    #svm_light conversion for training data
    with open(train_file, 'wb') as txtfile:
        for i in xrange(len(train)):
            converted_row = svm_light_conversion(train[i]) + '\n'

            txtfile.write(converted_row)

    txtfile.close()

    #svm_light conversion for test data#
    with open(test_file, 'wb') as txtfile:
        for i in xrange(len(test)):
            converted_row = svm_light_conversion(test[i]) + '\n'

            txtfile.write(converted_row)

    txtfile.close()



def main():

    inputfile = sys.argv[1]
    outputfile = sys.argv[2]

    content = reaData(inputfile)

    train, test = train_test_split(content, train_size = 0.8) #split data
    converToSVMLiteFormat(outputfile, train, test)



if __name__ == "__main__":
    main()

It was working absolutely fine before, but now suddenly its giving the error:

(env)fieldsofgold@fieldsofgold-VirtualBox:~/new$ python prac.py data.csv outt
Traceback (most recent call last):
  File "prac.py", line 4, in <module>
    from sklearn.cross_validation import train_test_split
  File "/home/fieldsofgold/new/env/local/lib/python2.7/site-packages/sklearn/cross_validation.py", line 32, in <module>
    from .metrics.scorer import check_scoring
  File "/home/fieldsofgold/new/env/local/lib/python2.7/site-packages/sklearn/metrics/__init__.py", line 7, in <module>
    from .ranking import auc
  File "/home/fieldsofgold/new/env/local/lib/python2.7/site-packages/sklearn/metrics/ranking.py", line 30, in <module>
    from ..utils.stats import rankdata
  File "/home/fieldsofgold/new/env/local/lib/python2.7/site-packages/sklearn/utils/stats.py", line 2, in <module>
    from scipy.stats import rankdata as _sp_rankdata
  File "/home/fieldsofgold/new/env/local/lib/python2.7/site-packages/scipy/stats/__init__.py", line 338, in <module>
    from .stats import *
  File "/home/fieldsofgold/new/env/local/lib/python2.7/site-packages/scipy/stats/stats.py", line 189, in <module>
    from . import distributions
  File "/home/fieldsofgold/new/env/local/lib/python2.7/site-packages/scipy/stats/distributions.py", line 10, in <module>
    from ._distn_infrastructure import (entropy, rv_discrete, rv_continuous,
  File "/home/fieldsofgold/new/env/local/lib/python2.7/site-packages/scipy/stats/_distn_infrastructure.py", line 44, in <module>
    from new import instancemethod
  File "/home/fieldsofgold/new/new.py", line 10, in <module>
    response2 = urllib2.urlopen(row[12])
  File "/usr/lib/python2.7/urllib2.py", line 127, in urlopen
    return _opener.open(url, data, timeout)
  File "/usr/lib/python2.7/urllib2.py", line 396, in open
    protocol = req.get_type()
  File "/usr/lib/python2.7/urllib2.py", line 258, in get_type
    raise ValueError, "unknown url type: %s" % self.__original
ValueError: unknown url type: 0.0

Could anyone please help me parse the error? It seems like the error occurs somewhere in sklearn but I do not understand completely what could be going wrong. Thanks.

Answer 1

If you follow the traceback, from the line in your file

from sklearn.cross_validation import train_test_split

you create a cascade of imports. But if you read later on in the traceback, you'll see this

    from new import instancemethod
  File "/home/fieldsofgold/new/new.py", line 10, in <module>

There is a module somewhere in Python called new.py . However, you have also created a module called new.py in your current directory. Because of the priority of imports , Python will first look for the module in the current working directory. If it doesn't find it, it will try other places, according to

>>> import sys
>>> sys.path

So basically Python imports the wrong new.py and it all snowballs from there. In order to avoid the problem, simply rename your new folder and the new.py file to something else. Also, make sure you delete the new.pyc file which has been created, because its existence is enough to attempt the import from there.

Just for the curious ones, this is the content of the file, located in .../Python27/Lib/ on Windows.

"""Create new objects of various types.  Deprecated.
This module is no longer required except for backward compatibility.
Objects of most types can now be created by calling the type object.
"""
from warnings import warnpy3k
warnpy3k("The 'new' module has been removed in Python 3.0; use the 'types' "
            "module instead.", stacklevel=2)
del warnpy3k

from types import ClassType as classobj
from types import FunctionType as function
from types import InstanceType as instance
from types import MethodType as instancemethod
from types import ModuleType as module

from types import CodeType as code