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What is the difference between NaN and None?
I am reading two columns of a csv file using pandas readcsv() and then assigning the values to a dictionary. The columns contain strings of numbers and letters. Occasionally there are cases where a cell is empty. In my opinion, the value read to that dictionary entry should be None but instead ...
Difference between git checkout --track origin/branch and git checkout -b branch origin/branch
Does anybody know the difference between these two commands to switch and track a remote branch?
4 Answers
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In Python how should I test if a variable is None, True or False
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Don't fear the Exception! Having your program just log and continue is as easy as:
try:
result = simulate(open("myfile"))
except SimulationException as sim_exc:
print "error parsing stream", sim_exc
else:
if result:
print "result pass"
else:
print...
What do 'lazy' and 'greedy' mean in the context of regular expressions?
Could someone explain these two terms in an understandable way?
12 Answers
12
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What is the difference between a var and val definition in Scala?
What is the difference between a var and val definition in Scala and why does the language need both? Why would you choose a val over a var and vice versa?
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Is there a performance gain in using single quotes vs double quotes in ruby?
...gle quotes in ruby decreases performance in any meaningful way in ruby 1.8 and 1.9.
14 Answers
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Why do function pointer definitions work with any number of ampersands '&' or asterisks '*'?
...foo)() = foo; works: foo is implicitly converted into a pointer to itself and that pointer is assigned to p1_foo.
The unary &, when applied to a function, yields a pointer to the function, just like it yields the address of an object when it is applied to an object. For pointers to ordinary f...
Python ElementTree module: How to ignore the namespace of XML files to locate matching element when
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Instead of modifying the XML document itself, it's best to parse it and then modify the tags in the result. This way you can handle multiple namespaces and namespace aliases:
from io import StringIO # for Python 2 import from StringIO instead
import xml.etree.ElementTree as ET
# instead of...
Centering a view in its superview using Visual Format Language
I just started learning AutoLayout for iOS and had a look at Visual Format Language.
14 Answers
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Android OpenGL ES and 2D
Well, here's my request. I don't know OpenGL already, and I'm not willing to learn it, I want to learn OpenGL ES directly since I'm targeting my development to android, however. I want to learn OpenGL ES in order to develop my 2D games. I chose it for performances purpose (since basic SurfaceView ...