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Is a Java string really immutable?
We all know that String is immutable in Java, but check the following code:
15 Answers
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How to get all subsets of a set? (powerset)
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The Python itertools page has exactly a powerset recipe for this:
from itertools import chain, combinations
def powerset(iterable):
"powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)"
s = list(iterable)
return chain.from_iterable(combinations(s, r)...
TemplateDoesNotExist - Django Error
I'm using Django Rest Framework. and I keep getting an error
5 Answers
5
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Task continuation on UI thread
Is there a 'standard' way to specify that a task continuation should run on the thread from which the initial task was created?
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Django import error - no module named django.conf.urls.defaults
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django.conf.urls.defaults has been removed in Django 1.6. If the problem was in your own code, you would fix it by changing the import to
from django.conf.urls import patterns, url, include
However, in your case the problem is in a ...
What is a “callable”?
...be called.
The built-in callable (PyCallable_Check in objects.c) checks if the argument is either:
an instance of a class with a __call__ method or
is of a type that has a non null tp_call (c struct) member which indicates callability otherwise (such as in functions, methods etc.)
The method n...
How to set a single, main title above all the subplots with Pyplot?
I am using pyplot . I have 4 subplots. How to set a single, main title above all the subplots? title() sets it above the last subplot.
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How to create a GUID/UUID in Python
How do I create a GUID in Python that is platform independent? I hear there is a method using ActivePython on Windows but it's Windows only because it uses COM. Is there a method using plain Python?
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PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
How do I modify the owner of all tables in a PostgreSQL database?
20 Answers
20
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Specifying colClasses in the read.csv
I am trying to specify the colClasses options in the read.csv function in R. In my data, the first column "time" is basically a character vector while the rest of the columns are numeric.
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