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Is there any difference between “foo is None” and “foo == None”?
... Hmmm, I think your link changed, unless you were interested in how to call external functions from python
– Pat
May 4 '12 at 20:39
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Assignment inside lambda expression in Python
I have a list of objects and I want to remove all objects that are empty except for one, using filter and a lambda expression.
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PyLint, PyChecker or PyFlakes? [closed]
...plus for everybody, but I like it ;-)
Cons of PyLint:
Some rules are really strict. I know that you can change it and that the default is to match PEP8, but is it such a crime to write 'for x in seq'? Apparently yes because you can't write a variable name with less than 3 letters. I will change ...
R command for setting working directory to source file location in Rstudio
... you should see the current working directory. To the right of that is a small arrow. Click that to show the current working directory in the file browser.
– Richie Cotton
Feb 20 at 15:40
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Error to install Nokogiri on OSX 10.9 Maverick?
I upgraded my OSX (Lion) to Mavericks and I can't install Nokogiri for my projects.
30 Answers
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if A vs if A is not None:
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The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...
How to create an array containing 1…N
...want an array of numbers 1..n that you can later loop through.
If this is all you need, can you do this instead?
var foo = new Array(45); // create an empty array with length 45
then when you want to use it... (un-optimized, just for example)
for(var i = 0; i < foo.length; i++){
document.w...
How do you detect where two line segments intersect? [closed]
...f r × s = 0 and (q − p) × r ≠ 0, then the two lines are parallel and non-intersecting.
If r × s ≠ 0 and 0 ≤ t ≤ 1 and 0 ≤ u ≤ 1, the two line segments meet at the point p + t r = q + u s.
Otherwise, the two line segments are not parallel but do not intersect....
Getting All Variables In Scope
Is there a way to get all variables that are currently in scope in javascript?
10 Answers
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How to make my custom type to work with “range-based for loops”?
...hanges, and compilers that do not.
The objects returned do not have to actually be iterators. The for(:) loop, unlike most parts of the C++ standard, is specified to expand to something equivalent to:
for( range_declaration : range_expression )
becomes:
{
auto && __range = range_expressi...