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Why does ~True result in -2?
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@ofcapl Just wanted to say: Although int('1') is also 1 but ~'1' be a typeerror exception whereas ~True is not this is because bool is a subclass of int @ Martijn added this information in his answer.
– Gri...
Format a date using the new date time API
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LocalDate represents just a date, not a DateTime. So "HH:mm:ss" make no sense when formatting a LocalDate. Use a LocalDateTime instead, assuming you want to represent both a date and time.
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Can I set a breakpoint on 'memory access' in GDB?
I am running an application through gdb and I want to set a breakpoint for any time a specific variable is accessed / changed. Is there a good method for doing this? I would also be interested in other ways to monitor a variable in C/C++ to see if/when it changes.
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What difference is there between WebClient and HTTPWebRequest classes in .NET?
...sing statements from both examples for brevity. You should definitely take care to dispose your web request objects properly.
In general, WebClient is good for quick and dirty simple requests and HttpWebRequest is good for when you need more control over the entire request.
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Running a specific test case in Django when your app has a tests directory
...ocs.djangoproject.com/en/1.3/topics/testing/#running-tests ) says that you can run individual test cases by specifying them:
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Search an Oracle database for tables with specific column names?
We have a large Oracle database with many tables. Is there a way I can query or search to find if there are any tables with certain column names?
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Bash, no-arguments warning, and case decisions
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if [[ $# -eq 0 ]] ; then
echo 'some message'
exit 0
fi
case "$1" in
1) echo 'you gave 1' ;;
*) echo 'you gave something else' ;;
esac
The Advanced Bash-Scripting Guide is pretty good. In spite of its name, it does treat the basics.
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Time complexity of Sieve of Eratosthenes algorithm
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Your n/2 + n/3 + n/5 + … n/97 is not O(n), because the number of terms is not constant. [Edit after your edit: O(n2) is too loose an upper bound.] A loose upper-bound is n(1+1/2+1/3+1/4+1/5+1/6+…1/n) (sum of reciprocals of all numbers up to n), which is O(n log n): se...
Creating functions in a loop
...h late binding -- each function looks up i as late as possible (thus, when called after the end of the loop, i will be set to 2).
Easily fixed by forcing early binding: change def f(): to def f(i=i): like this:
def f(i=i):
return i
Default values (the right-hand i in i=i is a default value...
What are the GCC default include directories?
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There is a command with a shorter output, which allows to automatically cut the include pathes from lines, starting with a single space:
$ echo | gcc -Wp,-v -x c++ - -fsyntax-only
ignoring nonexistent directory "/usr/lib/gcc/x86_64-redhat-linux/4.8.2/include-fixed"
ignoring nonexistent dir...