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Is it safe to check floating point values for equality to 0?
... to b".
It is not safe (because it is not correct) to expect that the result of some calculation will be zero in double (or more generally, floating point) arithmetics whenever the result of the same calculation in pure Mathematics is zero. This is because when calculations come into the ground, fl...
Failed to serialize the response in Web API with Json
I am working with ASP.NET MVC 5 Web Api. I want consult all my users.
27 Answers
27
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Display open transactions in MySQL
...ection:
If an automatic reconnection does occur (for example, as a result of calling mysql_ping()), there is no explicit indication of it. To check for reconnection, call mysql_thread_id() to get the original connection identifier before calling mysql_ping(), then call mysql_thread_id() again to...
System.Threading.Timer in C# it seems to be not working. It runs very fast every 3 second
... This does not guarantee that the code is called no less than <interval> after the last execution (a new tick of the timer could be fired a microsecond after a previous tick released the lock). It depends if this is a strict requirement or not (not entirely clear from the problem's...
Validate uniqueness of multiple columns
...umn? For example, a friendship model / table should not be able to have multiple identical records like:
3 Answers
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Naming convention for Scala constants?
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val UpperConst = "UPPER"
def main(args: Array[String]) {
for (i <- Seq(lowerConst, UpperConst, "should mismatch.").map(Option.apply)) {
print("Input '%s' results in: ".format(i))
i match {
case Some(UpperConst) => println("UPPER!!!")
case Some(lowerConst) ...
How to get scrollbar position with Javascript?
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You can use element.scrollTop and element.scrollLeft to get the vertical and horizontal offset, respectively, that has been scrolled. element can be document.body if you care about the whole page. You can compare it to element.offsetHeight and elemen...
Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...e reduce can operate on each chunk, then the reduce can operate on the results of each chunk - in fact the level of chunking need not stop one level deep. We could chop up each chunk too. This is why summing integers in a list is O(log N) if given an infinite number of CPUs.
If you just look at t...
Difference between 'new operator' and 'operator new'?
...ontainer, you can call operator new directly, like:
char *x = static_cast<char *>(operator new(100));
It's also possible to overload operator new either globally, or for a specific class. IIRC, the signature is:
void *operator new(size_t);
Of course, if you overload an operator new (eit...
Getting back old copy paste behaviour in tmux, with mouse
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To restore the default copy/paste configuration you need to (at least temporarily) turn off mouse support within tmux:
prefix : set -g mouse off
Where prefix is the tmux access key (Ctrl+B by default unless you re-map it). : starts command mo...