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Remove columns from dataframe where ALL values are NA
... quicker, as the colSum() solution seemed to be doing more work. But on my test set (213 obs. of 1614 variables before, vs. 1377 variables afterwards) it takes exactly 3 times longer. (But +1 for an interesting approach.)
– Darren Cook
Feb 17 '12 at 12:01
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Regex for string not ending with given suffix
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regexpal is a javascript based regex tester and javascript doesn't support lookbehind assertions which is sad
– HamZa
May 6 '13 at 12:58
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“Private” (implementation) class in Python
...erything public has its own awesome perks, like for instance, you can unit test pretty much anything from outside (which you can't really do with C/C++ private constructs).
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How do I get list of methods in a Python class?
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you can also import the FunctionType from types and test it with the class.__dict__:
from types import FunctionType
class Foo:
def bar(self): pass
def baz(self): pass
def methods(cls):
return [x for x, y in cls.__dict__.items() if type(y) == FunctionType]
metho...
What does 'predicate' mean in the context of computer science? [duplicate]
...f computer science, we aren't interested in stating a fact, but rather, in testing a true/false condition for the purpose of deciding whether to do something.
Person mike;
if (!mike.isEating())
feedPerson(mike);
The isEating() member of mike (an instance of Person) is a predicate. It return...
How do I remove a substring from the end of a string in Python?
... Yeah, I myself think that the first example, with the endswith() test, would be the better one; the regex one would involve some performance penalty (parsing the regex, etc.). I wouldn't go with the rsplit() one, but that's because I don't know what you're exactly trying to achieve. I figu...
MySQL “NOT IN” query
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In my own tests, had same performance for both NOT IN & LEFT JOIN. +1 both
– BufferStack
Jan 19 '12 at 11:45
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How do I get Gridview to render THEAD?
...iew by name instead of using the custom-gridview approach.
FYI: I haven't tested the footer logic, but I do know this works for Headers.
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Creating an instance using the class name and calling constructor
...quite that simple - I did look at the docs but was confused, but also if I tested it and it worked - ok then it worked - but if it didn't work then I would have been unsure if the problem was due to some lack of configuration or something on my part - often when asking such simple questions, people ...
What is the colon operator in Ruby?
...41)
sym == sym 0.180000 0.000000 0.180000 ( 0.179374)
Both symbol tests are basically the same as far as speed. After 1,000,000 iterations there's only 0.004733 second difference, so I'd say it's a wash between which to use.
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