In Python I am running code to define a function. the first part appears to run ok but the second part throws a 'name not defined' error.
Here is the code;` #This this part runs fine.
def modelfit(alg, dtrain, predictors, performCV=True, printFeatureImportance=True, cv_folds=5):
#Fit the algorithm on the data
alg.fit(dtrain[predictors], dtrain['Target'])
# the part below this is where the error gets thrown
# Predict training set:
dtrain_predictions = alg.predict(dtrain[predictors])
dtrain_predprob = alg.predict_proba(dtrain[predictors])[:,1]
Here is the complete error
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
<ipython-input-22-edfedf10fb86> in <module>()
1 #Predict training set:
----> 2 dtrain_predictions = alg.predict(dtrain[predictors])
3 dtrain_predprob = alg.predict_proba(dtrain[predictors])[:,1]
NameError: name 'alg' is not defined
What am I doing wrong?
It is because the indentation of this function definition is not aligned. The "alg" is a variable defined by the function "modelfit", and indented out of alignment is considered a new variable outside the function.What you shoule do is just to adjust the indentation.
Related
Could you help me understand what is going on here. The question is about the error in the traceback. The failure is just as the illustration. And what I would like to illustrate that the function works.
Well, I was told that 2 positional arguments: 'view_instance' and 'address' are missing.
But the method really has taken those 2 positional arguments and worked happily till its logical end. In the interactive playing I show that I can catch the arguments transmitted.
Why does error appear? Thank you in advance for your help.
ADDED LATER:
Well, this seems to be because of the 'test_' beginning of the function.
Without "test" it works (def anonymous_user_redirected_to_login_page(self, view_instance, address):).
/photoarchive/general/tests.py
class GeneralTest(TestCase):
def test_anonymous_user_redirected_to_login_page(self, view_instance, address):
pdb.set_trace()
request = RequestFactory().get(address)
request.user = AnonymousUser()
response = view_instance(request)
self.assertEqual(response.status_code, 302)
self.assertEqual(response['location'], '/accounts/login/')
def test_anonymous_user_from_home_page_redirected_to_login_page(self):
view_instance = HomePageView.as_view()
address = '/'
self.test_anonymous_user_redirected_to_login_page(view_instance, address)
Traceback
(photoarchive) michael#michael:~/workspace/photoarchive/photoarchive$ python manage.py test general
Creating test database for alias 'default'...
FE
======================================================================
ERROR: test_anonymous_user_redirected_to_login_page (general.tests.GeneralTest)
----------------------------------------------------------------------
TypeError: test_anonymous_user_redirected_to_login_page() missing 2 required positional arguments: 'view_instance' and 'address'
======================================================================
FAIL: test_anonymous_user_from_home_page_redirected_to_login_page (general.tests.GeneralTest)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/home/michael/workspace/photoarchive/photoarchive/general/tests.py", line 29, in test_anonymous_user_from_home_page_redirected_to_login_page
self.test_anonymous_user_redirected_to_login_page(view_instance, address)
File "/home/michael/workspace/photoarchive/photoarchive/general/tests.py", line 23, in test_anonymous_user_redirected_to_login_page
self.assertEqual(response.status_code, 302)
AssertionError: 200 != 302
----------------------------------------------------------------------
Ran 2 tests in 0.002s
FAILED (failures=1, errors=1)
Destroying test database for alias 'default'...
Interactive playing:
(photoarchive) michael#michael:~/workspace/photoarchive/photoarchive$ python manage.py test general
Creating test database for alias 'default'...
> /home/michael/workspace/photoarchive/photoarchive/general/tests.py(20)test_anonymous_user_redirected_to_login_page()
-> request = RequestFactory().get(address)
(Pdb) view_instance
<function HomePageView at 0x7faa0f76fea0>
(Pdb) address
'/'
(Pdb)
test_anonymous_user_redirected_to_login_page() method is treated by unittest framework as a test method, because its name starts with test. The framework tries to execute it, but is not passing any arguments to it (test methods don't normally take any arguments). However, the method requires them, hence the error.
If this method is only a helper method to be called from the other method, name it so that it doesn't start with test, e.g. _test_anonymous_user_redirected_to_login_page().
Note that the traceback is not related to this problem. The traceback simply shows where the other test method failed at an assertion. That is, the other test method runs correctly (both in unittest run and in your interactive session).
I'm trying to implement simple_tokenize using dictionary as the output from my previous code but i get an error message. Any assistance with the following code would be much appreciated. I'm using Python 2.7 Jupyter
import csv
reader = csv.reader(open('data.csv'))
dictionary = {}
for row in reader:
key = row[0]
dictionary[key] = row[1:]
print dictionary
The above works pretty well but issue is with the following:
import re
words = dictionary
split_regex = r'\W+'
def simple_tokenize(string):
for i in rows:
word = words.split
#pass
print word
I get this error:
NameError Traceback (most recent call last)
<ipython-input-2-0d0e05fb1556> in <module>()
1 import re
2
----> 3 words = dictionary
4 split_regex = r'\W+'
5
NameError: name 'dictionary' is not defined
Variables are not saved between Jupyter sessions, unless you explicitly do so yourself. Thus, if you ran the first code section, then quit your Jupyter session, started a new Jupyter session and ran the second code block, dictionary is not preserved from the first session and will thus be undefined, as indicated by the error.
If you run the above code blocks differently (e.g., not across Jupyter sessions), you should indicate this, but the tags and traceback suggest this is what you do.
Related to this question Command line arguments in python.
With the SYS module, how can I use a command line argument as a function name and function value, within my code - without importing some other module?
I'd like a solution that uses sys only. Also, please no variable-length params answers. Those are confusing. Assume that just the function name and one function variable are specified at the command line.
import sys
def reversal(aaa): return aaa[::-1]
a = sys.argv[1]
b = sys.argv[2]
print a(b)
At the command line
cpu_location$ python blah.py reversal 'abcdefg'
Traceback (most recent call last):
File "blah.py", line 8, in <module>
print a(b)
TypeError: 'str' object is not callable
I want to know how to make sys.argv[1] be considered a function name, thereby calling the function I have defined.
The other posts I see on this are a mash up of:
- dealing with C/C++ and adding some other module
- not using sys at all
- using the argv items as values for functions, and names of other files, instead of names of functions
Better than the eval solution would be:
a = globals()[sys.argv[1]]
a(b)
globals() returns a dictionary mapping global variables names to those global variables. So globals()['reversal'] evaluates to the reversal function.
It's safer than the eval function. With your approach you could do something like:
python blah.py 'lambda x: x+"hi"' foobar
Which would print foobarhi, which is unexpected because that's not a function name.
2 hours later, I find the answer. I think it's worth it to post it here in a very simple fashion.
Basiclaly there is no "function" data type in Python, but someone did mention a function eval, which is built-in. Execute python commands passed as strings in command line using python -c (No -c is needed for my own example)
The solution, is to change
a = sys.argv[1]
to
a = eval(sys.argv[1])
This will make the passed in word, reversal, be evaluated. It will evaluate to a function. Then the a(b) call will be a perfect call of a function on a string, like how it's defined. Output will be like:
cpu_location$ python blah.py reversal unquoted
detouqnu
cpu_location$ python blah.py reversal 'withquotes'
setouqhtiw
use google module: fire
pip install fire
Here's a simple example:
import fire
class Calculator(object):
"""A simple calculator class."""
def double(self, number):
return 2 * number
if __name__ == '__main__':
fire.Fire(Calculator)
Then, from the command line, you can run:
python calculator.py double 10 # 20
python calculator.py double --number=15 # 30
I have tried and run this script from Rutger Kassies.
import gdal
import matplotlib.pyplot as plt
ds = gdal.Open('HDF4_SDS:sample:"A2002037045000.L2_LAC.SAMPLE.hdf":01')
data = ds.ReadAsArray()
ds = None
fig, ax = plt.subplots(figsize=(6,6))
ax.imshow(data[0,:,:], cmap=plt.cm.Greys, vmin=1000, vmax=6000)
But then an error always occured:
Traceback (most recent call last):
File "D:\path\to\python\stackoverflow.py", line 5, in <module>
data = ds.ReadAsArray()
AttributeError: 'NoneType' object has no attribute 'ReadAsArray'
What's wrong with the script? Am I missing something? In installing GDAL I have followed this instruction http://pythongisandstuff.wordpress.com/2011/07/07/installing-gdal-and-ogr-for-python-on-windows/
Am using windows 7/32 bit/Python 2.7.
Thanks!
gdal.Open() is failing and returning 'None'. This produces the sometimes counterintuitive message "NoneType' object has no attribute ...". Quoting from Python: Attribute Error - 'NoneType' object has no attribute 'something', "NoneType means that instead of an instance of whatever Class or Object you think you're working with, you've actually got None. That usually means that an assignment or function call up above failed or returned an unexpected result."
Apparently GDAL is correctly installed. It could be that the file is not readable or that there is an issue with the HDF driver. Are you getting any error message like:
`HDF4_SDS:sample:"A2002037045000.L2_LAC.SAMPLE.hdf":01' does not
exist in the file system, and is not recognised as a supported dataset
name.
To get additional information you can try something like this instead of the gdal.Open() line in your script:
gdal.UseExceptions()
ds=None
try:
ds = gdal.Open('HDF4_SDS:sample:"A2002037045000.L2_LAC.SAMPLE.hdf":01')
except RuntimeError, err:
print "Exception: ", err
exit(1)
Also, there's an extra '}' at the end of the script.
By default, osgeo.gdal returns None on error, and does not normally raise informative exceptions. You can change this with gdal.UseExceptions().
Try something like this:
from osgeo import gdal
gdal.UseExceptions()
source_path = r'HDF4_SDS:sample:"D:\path\to\file\A2002037045000.L2_LAC.SAMPLE.hdf":01'
try:
ds = gdal.Open(source_path)
except RuntimeError as ex:
raise IOError(ex)
The last bit just re-raises the exception as an IOError rather than a RuntimeException.
The solution is to modify source_path to a working path to your data source, e.g., I see
IOError: `HDF4_SDS:sample:"A2002037045000.L2_LAC.SAMPLE.hdf":01' does not exist in the file system, and is not recognised as a supported dataset name.
import sys
def Hello(name):
name = name + '!!!'
print 'Hello' , name
def main():
Hello(sys.argv[1])
if __name__ == '__main__':
main()
Here is the error
Traceback (most recent call last):
File "D:\pythonPractice\firstPython.py", line 13, in <module>
main()
File "D:\pythonPractice\firstPython.py", line 9, in main
Hello(sys.argv[1])
IndexError: list index out of range
I have also tried sys.argv[2] but error remains
First things first, I think the code you originally posted (with Hello(sys.argv[0])) is not what you actually have. It doesn't match the error, which states sys.argv[1], so what you probably have is:
def main():
Hello(sys.argv[1])
As to the error then, it's because you haven't provided an argument when running. You need to do so, such that sys.argv[1] exists:
python helloprog Pax
You would find a more robust main as:
def main():
if len(sys.argv) < 2:
Hello("whoever you are")
else:
Hello(sys.argv[1])
which will detect when you haven't provided an argument, and use a suitable default rather than raising an exception.
Have you used
sys.argv[0]
Since this returns a list , you may not have elements >1