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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
Check if a number is int or float
...>> if isinstance(x, int):
print 'x is a int!'
x is a int!
_EDIT:_
As pointed out, in case of long integers, the above won't work. So you need to do:
>>> x = 12L
>>> import numbers
>>> isinstance(x, numbers.Integral)
True
>>> isinstance(x, int)
F...
Where to define custom error types in Ruby and/or Rails?
... error types in a Ruby library (gem) or Ruby on Rails application? Specifically:
5 Answers
...
How can I delete Docker's images?
...
In order to delete all images, use the given command
docker rmi $(docker images -q)
In order to delete all containers, use the given command
docker rm $(docker ps -a -q)
Warning: This will destroy all your images and containers. It will n...
How do I run Python code from Sublime Text 2?
... find out where your Break key is here: http://en.wikipedia.org/wiki/Break_key.
Note: CTRL + C will NOT work.
What to do when Ctrl + Break does not work:
Go to:
Preferences -> Key Bindings - User
and paste the line below:
{"keys": ["ctrl+shift+c"], "command": "exec", "args": {"k...
PHP Regex to get youtube video ID?
...y are very easy to make an error in, so if there are PHP functions specifically for what you are trying to accomplish, use those.)
parse_url takes a string and cuts it up into an array that has a bunch of info. You can work with this array, or you can specify the one item you want as a second argum...
Remove duplicate dict in list in Python
... {'a': 3222, 'b': 1234},
{'a': 123, 'b': 1234}]
seen = set()
new_l = []
for d in l:
t = tuple(d.items())
if t not in seen:
seen.add(t)
new_l.append(d)
print new_l
Example output:
[{'a': 123, 'b': 1234}, {'a': 3222, 'b': 1234}]
Note: As pointed out by @alexis ...
When should you use constexpr capability in C++11?
... "function that always returns 5" is breaking or diluting the meaning of "calling a function". There must be a reason, or a need for this capability or it wouldn't be in C++11. Why is it there?
...
Razor-based view doesn't see referenced assemblies
...m another project in the same solution (with assembly name MyCoreDBLayer). All objects from MyCore.DBLayer worked perfectly in Controllers and Models but failed in Razor views with an error 'The type or namespace name 'DBLayer' does not exist in the namespace 'MyCore' (are you missing an assembly re...
When is std::weak_ptr useful?
...want to keep them in memory, so you hold a strong pointer to them. Periodically, you scan the cache and decide which objects have not been accessed recently. You don't need to keep those in memory, so you get rid of the strong pointer.
But what if that object is in use and some other code holds a s...