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How to calculate the angle between a line and the horizontal axis?
...2(deltaY, deltaX) * 180 / PI
EDIT (Feb. 22, 2017): In general, however, calling atan2(deltaY,deltaX) just to get the proper angle for cos and sin may be inelegant. In those cases, you can often do the following instead:
Treat (deltaX, deltaY) as a vector.
Normalize that vector to a unit vector. ...
Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...ocking or asynchronous I/O is that your thread can continue its work in parallel. Of course you can achieve this also using an additional thread. As you stated for best overall (system) performance I guess it would be better to use asynchronous I/O and not multiple threads (so reducing thread switch...
JavaScript: How to pass object by value?
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Not really.
Depending on what you actually need, one possibility may be to set o as the prototype of a new object.
var o = {};
(function(x){
var obj = Object.create( x );
obj.foo = 'foo';
obj.bar = 'bar';
})(o);
aler...
java.lang.OutOfMemoryError: GC overhead limit exceeded [duplicate]
...) HashMap objects with a few (15-20) text entries each. These Strings have all to be collected (without breaking up into smaller amounts) before being submitted to a database.
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.NET unique object identifier
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I guess for lookups you'd have to iterate over all the references you track: WeakReference to the same object are not equal to each other, so you can't really do much else.
– Roman Starkov
Apr 23 '10 at 10:31
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What are the differences between “generic” types in C++ and Java?
...+" operator available.
In Java you have to specify a type if you want to call methods on the objects passed, something like:
<T extends Something> T sum(T a, T b) { return a.add ( b ); }
In C++ generic functions/classes can only be defined in headers, since the compiler generates different...
Disabled input text color
... opacity:1 is also necessary.
– Marcel Falliere
Aug 5 '15 at 10:01
3
Opacity isn't n...
Get String in YYYYMMDD format from JS date object?
... won't need the rightNow variable around, you can wrap new Date and get it all back in a single line: (new Date()).toISOString().slice(0,10).replace(/-/g,"")
– BigBlueHat
Sep 26 '13 at 17:43
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the item you requested is not available for purchase
...
Make sure to upload the signed APK to developer console.
Make sure to install the signed APK on your device not launch the app in the debugger.
Make sure to create a test account in your developer console.
Setup you testing account
Make sure to sign in your device with your test account.
In a cas...
Why git can't do hard/soft resets by path?
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Personally, I think git checkout -- <path> should be replaced with git reset --hard <path>. It makes so much more sense...
– vergenzt
Jun 26 '12 at 13:04
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