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How to work with complex numbers in C?
...h:
creal(z1): get the real part (for float crealf(z1), for long double creall(z1))
cimag(z1): get the imaginary part (for float cimagf(z1), for long double cimagl(z1))
Another important point to remember when working with complex numbers is that functions like cos(), exp() and sqrt() must be repl...
Java abstract interface
...blic void interfacing();
public abstract boolean interfacing(boolean really);
\___.__/
|
'----> nor this, are necessary.
}
Interfaces and their methods are implicitly abstract and adding that modifier makes no difference.
Is there other rules tha...
How to find all the subclasses of a class given its name?
I need a working approach of getting all classes that are inherited from a base class in Python.
10 Answers
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How to retrieve a module's path?
...
import a_module
print(a_module.__file__)
Will actually give you the path to the .pyc file that was loaded, at least on Mac OS X. So I guess you can do:
import os
path = os.path.abspath(a_module.__file__)
You can also try:
path = os.path.dirname(a_module.__file__)
To ge...
How do I get a list of column names from a psycopg2 cursor?
... to generate column labels directly from the selected column names, and recall seeing that python's psycopg2 module supports this feature.
...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...me byte code for while(True): pass and while(1): pass , but this is actually not the case in python2.7.
3 Answers
...
How to obtain the number of CPUs/cores in Linux from the command line?
... Note that both of these will end up counting twice as many cores as actually exist if you're on a system with hyperthreading (e.g, P4, or Core i7).
– duskwuff -inactive-
Jun 26 '11 at 0:04
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Number of elements in a javascript object
...
Although JS implementations might keep track of such a value internally, there's no standard way to get it.
In the past, Mozilla's Javascript variant exposed the non-standard __count__, but it has been removed with version 1.8.5.
For cross-browser scripting you're stuck with explicitly ite...
Execution of Python code with -m option or not
...st python -m foo.bar.baz
foo.bar
__main__
As a result, Python has to actually care about packages when using the -m switch. A normal script can never be a package, so __package__ is set to None.
But run a package or module inside a package with -m and now there is at least the possibility of a pac...
How can I quickly sum all numbers in a file?
...
For a Perl one-liner, it's basically the same thing as the awk solution in Ayman Hourieh's answer:
% perl -nle '$sum += $_ } END { print $sum'
If you're curious what Perl one-liners do, you can deparse them:
% perl -MO=Deparse -nle '$sum += $_ } END ...