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Equation for testing if a point is inside a circle
If you have a circle with center (center_x, center_y) and radius radius , how do you test if a given point with coordinates (x, y) is inside the circle?
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C++ Build Systems - What to use? [closed]
...looking at starting a new project in C++ - just in my own time initially - and I'm investigating the build systems that are available. It would appear that the answer is "Many, and they're all awful".
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How do I determine whether an array contains a particular value in Java?
...the searching functions in the Arrays class versus iterating over an array and using an equals() function or == for primitives.
– Thomas Owens
Jul 15 '09 at 0:06
188
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Printing HashMap In Java
...y returns a set of keys from your hashmap, you should iterate this key set and the get the value from the hashmap using these keys.
In your example, the type of the hashmap's key is TypeKey, but you specified TypeValue in your generic for-loop, so it cannot be compiled. You should change it to :
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How to find serial number of Android device?
I need to use a unique ID for an Android app and I thought the serial number for the device would be a good candidate. How do I retrieve the serial number of an Android device in my app ?
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How to nicely format floating numbers to String without unnecessary decimal 0?
...f the idea is to print integers stored as doubles as if they are integers, and otherwise print the doubles with the minimum necessary precision:
public static String fmt(double d)
{
if(d == (long) d)
return String.format("%d",(long)d);
else
return String.format("%s",d);
}
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How to search DOM elements using XPath or CSS selectors in Chrome Developer Tools?
...ntext) This allows you to select a particular iframe content, for example, and run an xpath query against it. So for the first iframe: myframe = document.getElementsByTagName("iframe")[0].contentWindow.document.body; #to xpath query that iframe for table cells: $x("//td",myframe);
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What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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What is the difference between ${var}, “$var”, and “${var}” in the Bash shell?
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Braces ($var vs. ${var})
In most cases, $var and ${var} are the same:
var=foo
echo $var
# foo
echo ${var}
# foo
The braces are only needed to resolve ambiguity in expressions:
var=foo
echo $varbar
# Prints nothing because there is no variable 'varbar'
echo ${var}bar...
How to get visitor's location (i.e. country) using geolocation? [duplicate]
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@juanpastas you don't. you just ping a service, and service will know. or you write service yourself, but that's out of pure javascript scope.
– tishma
Nov 7 '14 at 22:56
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