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How to calculate an angle from three points? [closed]
... is the vertex of then using the Law of Cosines should work:
arccos((P122
+ P132 - P232) / (2 *
P12 * P13))
where P12 is the length of the segment from P1 to P2, calculated by
sqrt((P1x -
P2x)2 +
(P1y -
P2y)2)
...
How to merge dictionaries of dictionaries?
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29 Answers
29
Active
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How to map and remove nil values in Ruby
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27
Ruby 2.7+
There is now!
Ruby 2.7 is introducing filter_map for this exact purpose. It's idiom...
Installing SetupTools on 64-bit Windows
I'm running Python 2.7 on Windows 7 64-bit, and when I run the installer for setuptools it tells me that Python 2.7 is not installed. The specific error message is:
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How can I remove the decimal part from JavaScript number?
...g a bitwise operator on a number is it will treat its operand as a signed 32bit integer, therefore removing the fractional component. Keep in mind this will also mangle numbers larger than 32 bits.
You may also be talking about the inaccuracy of decimal rounding with floating point arithmetic.
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Convert a float64 to an int in Go
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213
package main
import "fmt"
func main() {
var x float64 = 5.7
var y int = int(x)
fmt.Print...
How many characters can UTF-8 encode?
If UTF-8 is 8 bits, does it not mean that there can be only maximum of 256 different characters?
10 Answers
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How can I do an asc and desc sort using underscore.js?
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You can use .sortBy, it will always return an ascending list:
_.sortBy([2, 3, 1], function(num) {
return num;
}); // [1, 2, 3]
But you can use the .reverse method to get it descending:
var array = _.sortBy([2, 3, 1], function(num) {
return num;
});
console.log(array); // [1, 2, 3]
con...
Cast List to List in .NET 2.0
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.NET 2.0 has the ConvertAll method where you can pass in a converter function:
List<int> l1 = new List<int>(new int[] { 1, 2, 3 } );
List<string> l2 = l1.ConvertAll<string>(delegate(int i) { return i.To...