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Clang vs GCC - which produces faster binaries? [closed]
...25 |
The points of note here are:
Neither compiler now benefits at all from -O3 optimization.
Clang beats GCC just as importantly at each level of optimization.
GCC's performance is only marginally affected by the smart-pointer type
change.
Clang's -O2 performance is importantly affected by the...
Skip first entry in for loop in python?
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The best way to skip the first item(s) is:
from itertools import islice
for car in islice(cars, 1, None):
# do something
islice in this case is invoked with a start-point of 1, and an end point of None, signifying the end of the iterator.
To be able to skip ite...
Safe (bounds-checked) array lookup in Swift, through optional bindings?
...on because you would break all the code that expects a non-optional values from arrays.
Instead, you could subclass Array, and override subscript to return an optional. Or, more practically, you could extend Array with a non-subscript method that does this.
extension Array {
// Safely lookup ...
What are the complexity guarantees of the standard containers?
... O(n)
vector<T> v(begin, end); Make a vector and copy the elements from begin to end. O(n)
Accessors
v[i] Return (or set) the I'th element. O(1)
v.at(i) Return (or set) the I'th element, with bounds checking. O(1)
v.size() Return current numb...
C# Java HashMap equivalent
Coming from a Java world into a C# one is there a HashMap equivalent? If not what would you recommend?
7 Answers
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Get Substring between two characters using javascript
I am trying to extract a string from within a larger string where it get everything inbetween a ':' and a ';'.
16 Answers
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Eclipse Kepler for OS X Mavericks request Java SE 6
... After this I had a the error "App can't be opened because it is from an unidentified developer", the following question has the solution: stackoverflow.com/questions/19551298/…
– Jonoabroad
Oct 31 '13 at 3:01
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C++11 std::threads vs posix threads
...ement is boost::thread - it is very similar to std::thread (actually it is from the same author) and works reliably, but, of course, it introduces another dependency from a third party library.
Edit: As of 2017, std::thread mostly works on native Android. Some classes, like std::timed_mutex are s...
Why is $$ returning the same id as the parent process?
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$$ is defined to return the process ID of the parent in a subshell; from the man page under "Special Parameters":
$ Expands to the process ID of the shell. In a () subshell, it expands to the process ID of the current shell, not the subshell.
In bash 4, you can get the process ID...
Return multiple columns from pandas apply()
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This is an old question, but for completeness, you can return a Series from the applied function that contains the new data, preventing the need to iterate three times. Passing axis=1 to the apply function applies the function sizes to each row of the dataframe, returning a series to add to a n...