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C++: How to round a double to an int? [duplicate]
....
float x = 55; // stored as 54.999999...
x = x + 0.5 - (x<0); // x is now 55.499999...
int y = (int)x; // truncated to 55
C++11 also introduces std::round, which likely uses a similar logic of adding 0.5 to |x| under the hood (see the link if interested) but is obviously more robust.
A follo...
How to get element by class name? [duplicate]
... first one use:
document.getElementsByClassName('class_name')[0]
UPDATE
Now you can use:
document.querySelector(".class_name") to get the first element with the class_name CSS class (null will be returned if non of the elements on the page has this class name)
or document.querySelectorAll(".cla...
How to compare variables to undefined, if I don’t know whether they exist? [duplicate]
...iable and if it’s undefined , you can check variable == undefined ; I know that, but how can you compare a value that you don’t know yet if it’s in memory?
...
How to test if parameters exist in rails
...I, but I'm sure that's safe enough. I've been calling params.to_h.key? for now.
– stephen.hanson
Nov 9 '16 at 19:38
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show 12 more comments
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How do I get an empty array of any size in python?
...swering the question for readers in the future, not just the person asking now. Please edit your answer to add explanations and give an indication of what limitations and assumptions apply.
– Xnero
Jun 24 at 12:01
...
How can I stop a running MySQL query?
I connect to mysql from my Linux shell. Every now and then I run a SELECT query that is too big. It prints and prints and I already know this is not what I meant. I would like to stop the query.
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Putting a simple if-then-else statement on one line [duplicate]
...
Better Example: (thanks Mr. Burns)
'Yes' if fruit == 'Apple' else 'No'
Now with assignment and contrast with if syntax
fruit = 'Apple'
isApple = True if fruit == 'Apple' else False
vs
fruit = 'Apple'
isApple = False
if fruit == 'Apple' : isApple = True
...
Where does PHP's error log reside in XAMPP?
...side the vm (which took me an embarassingly long time to realise). I only know how to access via the xampp control panel terminal, with a path of: /opt/lampp/logs/php_error_log
– Scott Anderson
Apr 13 '19 at 14:16
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How do I get the calling method name and type using reflection? [duplicate]
...var type = method.DeclaringType;
var name = method.Name;
}
}
Now let's say you have another class like this:
public class Caller
{
public void Call()
{
SomeClass s = new SomeClass();
s.SomeMethod();
}
}
name will be "Call" and type will be "Caller"
UPDATE Two y...
How to replace an item in an array with Javascript?
...edle) {
return !!~haystack.indexOf(needle);
};
// can be used like so now:
if (contains(items, 3452)) {
// do something else...
}
Starting with ES6/ES2015 for strings, and proposed for ES2016 for arrays, you can more easily determine if a source contains another value:
if (haystack.inclu...