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Is it better to use std::memcpy() or std::copy() in terms to performance?
...y.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the m...
Get a list of checked checkboxes in a div using jQuery
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Unnecessary call of constructor var selected = new Array();. Better (cheaper) with var selected = [];
– Pono
Mar 17 '14 at 22:45
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Unresolved reference issue in PyCharm
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Manually adding it as you have done is indeed one way of doing this, but there is a simpler method, and that is by simply telling pycharm that you want to add the src folder as a source root, and then adding the sources root to y...
How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
Benchmarking (python vs. c++ using BLAS) and (numpy)
...e python for my program, what could I do to increase the performance when calling BLAS or LAPACK routines?
Make sure that numpy uses optimized version of BLAS/LAPACK libraries on your system.
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Python's many ways of string formatting — are the older ones (going to be) deprecated?
...ormatting syntax is more flexible and handles tuples and dictionaries naturally, it is recommended for new code. However, there are no current plans to deprecate printf-style formatting.
(Emphasis mine.)
This phrase was removed later, in commit Close #4966: revamp the sequence docs in order to be...
Using a piano keyboard as a computer keyboard [closed]
I have RSI problems and have tried 30 different computer keyboards which all caused me pain. Playing piano does not cause me pain. I have played piano for around 20 years without any pain issues. I would like to know if there is a way to capture MIDI from a MIDI keyboard and output keyboard stroke...
How would I run an async Task method synchronously?
I'm learning about async/await, and ran into a situation where I need to call an async method synchronously. How can I do that?
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How can I parse a YAML file from a Linux shell script?
...:// (for URLs)
s/$/"/g appends " to the end of each line
s/ *=/=/g removes all spaces before =
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Add new field to every document in a MongoDB collection
...field" : 1, "test" : "a" }
EDIT:
In case you want to add a new_field to all your collection, you have to use empty selector, and set multi flag to true (last param) to update all the documents
db.your_collection.update(
{},
{ $set: {"new_field": 1} },
false,
true
)
EDIT:
In the above ...