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Finding quaternion representing the rotation from one vector to another
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Be aware that this does not handle the case of parallel vectors (both in the same direction or pointing in opposite directions). crossproduct will not be valid in these cases, so you first need to check dot(v1, v2) > 0.999999 and dot(v1, v2) < -0.999999, respectively, ...
C++ equivalent of StringBuffer/StringBuilder?
...f after profiling your code you discover this makes an improvement.
I normally use either std::string or std::stringstream. I have never had any problems with these. I would normally reserve some room first if I know the rough size of the string in advance.
I have seen other people make their ow...
Python exit commands - why so many and when should each be used?
...s functionality was included to help people who do not know Python. After all, one of the most likely things a newbie will try to exit Python is typing in quit.
Nevertheless, quit should not be used in production code. This is because it only works if the site module is loaded. Instead, this fun...
What is the difference between “#!/usr/bin/env bash” and “#!/usr/bin/bash”?
...en Ubuntu 16.04 if not later).
Another downside is that since you aren't calling an explicit executable, it's got the potential for mistakes, and on multiuser systems security problems (if someone managed to get their executable called bash in your path, for example).
#!/usr/bin/env bash #lends yo...
Using property() on classmethods
... (using the classmethod() function) for getting and setting what is essentially a static variable. I tried to use the property() function with these, but it results in an error. I was able to reproduce the error with the following in the interpreter:
...
How can I obfuscate (protect) JavaScript? [closed]
... use:
Google Closure Compiler
UglifyJS
UPDATE: This question was originally asked more than 10 years ago, and YUI is no longer maintained. Google Closure Compiler is still in use, and UglifyJS can be run locally via node package manager: npm install -g uglify-js
Private String Data:
Keeping st...
DynamoDB vs MongoDB NoSQL [closed]
...roughput, you just click a button. You can write scripts to scale automatically. When it's time to upgrade Dynamo, it's done for you. That is all a lot of precious stress and time not spent. If you don't have dedicated ops people, Dynamo is excellent.
So we are now going on Dynamo by default. Mongo...
Prevent onmouseout when hovering child element of the parent absolute div WITHOUT jQuery
...Listener('mouseout',onMouseOut,true);
I made a quick JsFiddle demo, with all the CSS and HTML needed, check it out...
EDIT FIXED link for cross-browser support http://jsfiddle.net/RH3tA/9/
NOTE that this only checks the immediate parent, if the parent div had nested children then you have to s...
How to load up CSS files using Javascript?
...
Here's the "old school" way of doing it, which hopefully works across all browsers. In theory, you would use setAttribute unfortunately IE6 doesn't support it consistently.
var cssId = 'myCss'; // you could encode the css path itself to generate id..
if (!document.getElementById(cssId))
{
...
Objective-C for Windows
...X so that any viable OS X program can run on Windows. Because GNUStep typically uses the latest version of gcc, they also add in support for Objective-C++ and a lot of the Objective-C 2.0 features.
I haven't tested those features with GNUStep, but if you use a sufficiently new version of gcc, you m...