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Python Dictionary Comprehension
...>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple keys at once on an existing dictionary. ...
How to import module when module name has a '-' dash or hyphen in it?
...appens with sys.modules, you don't need it to import itself), just getting all of the file's globals into your own scope, you can use execfile
# contents of foo-bar.py
baz = 'quux'
>>> execfile('foo-bar.py')
>>> baz
'quux'
>>>
...
Is inline assembly language slower than native C++ code?
...
Yes, most times.
First of all you start from wrong assumption that a low-level language (assembly in this case) will always produce faster code than high-level language (C++ and C in this case). It's not true. Is C code always faster than Java code? N...
Delete column from pandas DataFrame
...
This answer isn't really correct - the pandas developers didn't, but that doesn't mean it is hard to do.
– wizzwizz4
Sep 30 '17 at 9:42
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Passing a std::array of unknown size to a function
...way to make this work, as one would with plain C-style arrays?
No. You really cannot do that unless you make your function a function template (or use another sort of container, like an std::vector, as suggested in the comments to the question):
template<std::size_t SIZE>
void mulArray(std:...
How to compile a static library in Linux?
...:
target: prerequisites - the rule head
$@ - means the target
$^ - means all prerequisites
$< - means just the first prerequisite
ar - a Linux tool to create, modify, and extract from archives see the man pages for further information. The options in this case mean:
r - replace files existing...
How can I read a function's signature including default argument values?
...
@Spi, you are calling inspect.getargspec on a module, not a function.
– Mike Graham
Apr 20 '10 at 17:36
...
Verifying that a string contains only letters in C#
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This assumes a latin alphabet, where Char.IsLetter allows for non-latin alphabets.
– Paul van Brenk
Jul 28 '09 at 7:31
5
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Why are preprocessor macros evil and what are the alternatives?
I have always asked this but I have never received a really good answer; I think that almost any programmer before even writing the first "Hello World" had encountered a phrase like "macro should never be used", "macro are evil" and so on, my question is: why? With the new C++11 is there a real alte...
I want to get the type of a variable at runtime
...that comparison return true, but it would require a few book chapters to really cover TypeTag, so I'll stop here.
Finally, maybe you don't care about the type of the variable at all. Maybe you just want to know what is the class of a value, in which case the answer is rather simple:
val x = 5
x.ge...