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Analyze audio using Fast Fourier Transform
...efficients you get out will be imaginary numbers even though your input is all real values. In order to get the amount of power in each frequency, you need to calculate the magnitude of the FFT coefficient for each frequency. This is not just the real component of the coefficient, you need to calcul...
How can I get a view's current width and height when using autolayout constraints?
...our existing constraints, the answer is not to inspect the constraints manually, since that would require you to re-implement the entire constraint-solving logic of the auto layout system in order to interpret those constraints. Instead, what you should do is just ask auto layout to update that layo...
Are inline virtual functions really a non-sense?
... excerpt from the excellent C++ faq:
"The only time an inline virtual call
can be inlined is when the compiler
knows the "exact class" of the object
which is the target of the virtual
function call. This can happen only
when the compiler has an actual object
rather than a pointer or ...
Unable to Cast from Parent Class to Child Class
...
Well, I would hesitate to call this a "downcast".
– Kirk Woll
Dec 24 '12 at 4:43
...
What is the optimal length for user password salt? [closed]
Any salt at all will obviously help when salting and hashing a user's password. Are there any best practices for how long the salt should be? I'll be storing the salt in my user table, so I would like the best tradeoff between storage size and security. Is a random 10 character salt enough? Or ...
Why does an SSH remote command get fewer environment variables then when run manually? [closed]
...e -i option. PS1 is
set and $- includes i if bash is interactive, allowing a
shell script or a startup file to test this state.
The following paragraphs describe how bash executes its
startup files. If any of the files exist but cannot be
read, bash rep...
X-UA-Compatible is set to IE=edge, but it still doesn't stop Compatibility Mode
...in the <head> element. No other meta tags, css links and js scripts calls can be placed before it.
<head>
<title>Site Title</title>
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
<meta charset="utf-8">
<script type="text/javascri...
What is console.log?
...
Places you can view the console! Just to have them all in one answer.
Firefox
http://getfirebug.com/
(you can also now use Firefox's built in developer tools Ctrl+Shift+J (Tools > Web Developer > Error Console), but Firebug is much better; use Firebug)
Safari and Ch...
Differences between unique_ptr and shared_ptr [duplicate]
...
Both of these classes are smart pointers, which means that they automatically (in most cases) will deallocate the object that they point at when that object can no longer be referenced. The difference between the two is how many different pointers of each type can refer to a resource.
When using...
What is the HEAD in git?
...ce to the last commit in the currently checked-out branch.
There is a small exception to this, which is the detached HEAD. A detached HEAD is the situation you end up in whenever you check out a commit (or tag) instead of a branch. In this case, you have to imagine this as a temporary branch with...