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UnboundLocalError on local variable when reassigned after first use
...f you want to modify it, you have to use the global keyword. Try changing test() to this:
def test():
global c
print(a)
print(b)
print(c) # (A)
c+=1 # (B)
Also, the reason you are getting this error is because you can also declare a new variable inside that function...
Character reading from file in Python
...iles in update mode, allowing both reading and writing:
with codecs.open('test', encoding='utf-8', mode='w+') as f:
f.write(u'\u4500 blah blah blah\n')
f.seek(0)
print repr(f.readline()[:1])
EDIT: I'm assuming that your intended goal is just to be able to read the file properly into a...
What should I do if two libraries provide a function with the same name generating a conflict?
...ATE: I just did it on this end and it seems to work. Of course, I've not tested this thoroughly - it may be no more than a really good way to blow your leg off with a hexedit shotgun.
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Alarm Manager Example
...ntService::class.java)
intent.action = MyIntentService.ACTION_SEND_TEST_MESSAGE
intent.putExtra(MyIntentService.EXTRA_MESSAGE, message)
pendingIntent = PendingIntent.getService(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)
alarmManager.set(AlarmManager.RTC_W...
pandas dataframe columns scaling with sklearn
...import MinMaxScaler
>>> scaler = MinMaxScaler()
>>> dfTest = pd.DataFrame({'A':[14.00,90.20,90.95,96.27,91.21],
'B':[103.02,107.26,110.35,114.23,114.68],
'C':['big','small','big','small','small']})
>>> dfTest[['A', ...
Share Large, Read-Only Numpy Array Between Multiprocessing Processes
...n use numpy.memmap. For example, if you have an array stored in disk, say 'test.array', you can use simultaneous processes to access the data in it even in "writing" mode, but your case is simpler since you only need "reading" mode.
Creating the array:
a = np.memmap('test.array', dtype='float32', ...
Javascript switch vs. if…else if…else
..., because each has a different JS processing engine, however, in running a test on the site below, the switch always out performed the if, elseif on a large number of iterations.
Test site
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How to set size for local image using knitr for markdown?
...
Does not work for me either, on the latest version of all packages.
– slhck
Sep 29 '17 at 12:16
3
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How to get progress from XMLHttpRequest
... server script reads a zip file (it takes 5 seconds):
$filesize=filesize('test.zip');
header("Content-Length: " . $filesize); // set header length
// if the headers is not set then the evt.loaded will be 0
readfile('test.zip');
exit 0;
Now I can monitor the download process of the server script,...
Serving gzipped CSS and JavaScript from Amazon CloudFront via S3
...load a gzip and non-gzip version of the css and js. Be careful naming and test in Safari. Because safari won't handle .css.gz or .js.gz files.
site.js and site.js.jgz and
site.css and site.gz.css (you'll need to set the content-encoding header to the correct MIME type to get these to serve ri...