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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...
private[this] vs private
...rotected over public doesn't apply.
Use private[this] where performance really matters (since you'll get direct field access instead of methods this way). Otherwise, just settle on one style so people don't need to figure out why this property is private and that one is private[this].
...
How to use single storyboard uiviewcontroller for multiple subclass
...do what you propose because there are no initializers in UIStoryboard that allow overriding the view controller associated with the storyboard as defined in the object details in the storyboard on initialization. It's at initialization that all the UI elements in the stoaryboard are linked up to th...
Is there a short contains function for lists?
...her have said, you may also be interested to know that what in does is to call the list.__contains__ method, that you can define on any class you write and can get extremely handy to use python at his full extent.
A dumb use may be:
>>> class ContainsEverything:
def __init__(self):...
Counting array elements in Python [duplicate]
... in an array, because contrary to logic array.count(string) does not count all the elements in the array, it just searches for the number of occurrences of string.
...
Delete files older than 15 days using PowerShell
...is in the title of this post), but here's some code that will first delete all of the files older than 15 days, and then recursively delete any empty directories that may have been left behind. My code also uses the -Force option to delete hidden and read-only files as well. Also, I chose to not use...
libpthread.so.0: error adding symbols: DSO missing from command line
...nd line after the object files being compiled:
gcc -Wstrict-prototypes -Wall -Wno-sign-compare -Wpointer-arith -Wdeclaration-after-statement -Wformat-security -Wswitch-enum -Wunused-parameter -Wstrict-aliasing -Wbad-function-cast -Wcast-align -Wstrict-prototypes -Wold-style-definition -Wmissing-pr...
TypeError: 'NoneType' object is not iterable in Python
... Correct, But the common scenario author intended here is totally to skip the for loop instead of raising an exception. Python's design is flawed here. When None is treated as an iterable it must return empty list at least. This exception never helped anyone in real life other than m...
Can PostgreSQL index array columns?
... to this question in the documentation. If a column is an array type, will all the entered values be individually indexed?
...
Javascript - How to detect if document has loaded (IE 7/Firefox 3)
I want to call a function after a document loads, but the document may or may not have finished loading yet. If it did load, then I can just call the function. If it did NOT load, then I can attach an event listener. I can't add an eventlistener after onload has already fired since it won't get cal...