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Attempt to present UIViewController on UIViewController whose view is not in the window hierarchy
Just started using Xcode 4.5 and I got this error in the console:
33 Answers
33
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How do I calculate a point on a circle’s circumference?
... r * cos(a)
y = cy + r * sin(a)
Where r is the radius, cx,cy the origin, and a the angle.
That's pretty easy to adapt into any language with basic trig functions. Note that most languages will use radians for the angle in trig functions, so rather than cycling through 0..360 degrees, you're cycli...
Implement paging (skip / take) functionality with this query
I have been trying to understand a little bit about how to implement custom paging in SQL, for instance reading articles like this one .
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Difference between std::system_clock and std::steady_clock?
What is the difference between std::system_clock and std::steady_clock ? (An example case that illustrate different results/behaviours would be great).
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When is del useful in python?
I can't really think of any reason why python needs the del keyword (and most languages seem to not have a similar keyword). For instance, rather than deleting a variable, one could just assign None to it. And when deleting from a dictionary, a del method could be added.
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405 method not allowed Web API
This error is very common, and I tried all of the solutions and non of them worked. I have disabled WebDAV publishing in control panel and added this to my web config file:
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Breaking loop when “warnings()” appear in R
... I am running a loop to process multiple files. My matrices are enormous and therefore I often run out of memory if I am not careful.
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Measuring text height to be drawn on Canvas ( Android )
...it now is by using Paint's measureText() to get the width, then by trial and error finding a value to get an approximate height. I've also been messing around with FontMetrics , but all these seem like approximate methods that suck.
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How do I convert a double into a string in C++?
...y:
std::string str = boost::lexical_cast<std::string>(dbl);
The Standard C++ way:
std::ostringstream strs;
strs << dbl;
std::string str = strs.str();
Note: Don't forget #include <sstream>
share
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What is the expected syntax for checking exception messages in MiniTest's assert_raises/must_raise?
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@thanikkal Make sure you are using Minitest::Spec and not Minitest::Test. The Spec DSL, including expectations, are only available when using Minitest::Spec.
– blowmage
Oct 10 '16 at 15:28
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