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Convert to absolute value in Objective-C
...), fabsf(float), fabs(double), or fabsl(long double).
Those functions are all part of the C standard library, and so are present both in Objective-C and plain C (and are generally available in C++ programs too.)
(Alas, there is no habs(short) function. Or scabs(signed char) for that matter...)
...
Hashing a dictionary?
...e hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach might not produce a stable result.
...
Tri-state Check box in HTML?
...ment, I found a better solution:
HTML5 defines a property for checkboxes called indeterminate
See w3c reference guide. To make checkbox appear visually indeterminate set it to true:
element.indeterminate = true;
Here is Janus Troelsen's fiddle. Note, however, that:
The indeterminate state can...
Grepping a huge file (80GB) any way to speed it up?
...
Here are a few options:
1) Prefix your grep command with LC_ALL=C to use the C locale instead of UTF-8.
2) Use fgrep because you're searching for a fixed string, not a regular expression.
3) Remove the -i option, if you don't need it.
So your command becomes:
LC_ALL=C fgrep -A 5 -...
moving changed files to another branch for check-in
... you have not made the commit yet, just run git stash. This will save away all of your changes.
Switch to the branch you want the changes on and run git stash pop.
There are lots of uses for git stash. This is certainly one of the more useful reasons.
An example:
# work on some code
git stash
gi...
Do try/catch blocks hurt performance when exceptions are not thrown?
... {
Console.WriteLine(ex.ToString());
}
finally
{
d = Math.Sin(d);
}
}
w.Stop();
Console.Write(" try/catch/finally: ");
Console.WriteLine(w.ElapsedMilliseconds);
w.Reset();
d = 0;
w.Start();
for (int i = ...
Why can't the C# constructor infer type?
...type inference?
No. When you have
new Foo(bar)
then we could identify all types called Foo in scope regardless of generic arity, and then do overload resolution on each using a modified method type inference algorithm. We'd then have to create a 'betterness' algorithm that determines which of t...
Convert SQLITE SQL dump file to POSTGRESQL
...h a sequence to that column so that INSERTs with NULL ids will be automatically assigned the next available value. PostgreSQL will also not recognize AUTOINCREMENT commands, so these need to be removed.
You'll also want to check for datetime columns in the SQLite schema and change them to timestamp ...
LINQ - Left Join, Group By, and Count
...
.Count() will generate COUNT(*) which will count all the rows in that group, by the way.
– Mehrdad Afshari
Mar 29 '09 at 22:47
...
tinyxml XML解析库下载（tinyxml2.h 和 tinyxml2.cpp） - 源码下载 - 清泛...
...>
# include <cstdarg>
#endif
/*
TODO: intern strings instead of allocation.
*/
/*
gcc:
g++ -Wall -DDEBUG tinyxml2.cpp xmltest.cpp -o gccxmltest.exe
Formatting, Artistic Style:
AStyle.exe --style=1tbs --indent-switches --break-closing-brackets --indent-preproce...