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How to get all subsets of a set? (powerset)
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The Python itertools page has em>x m>actly a powerset recipe for this:
from itertools import chain, combinations
def powerset(iterable):
"powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)"
s = list(iterable)
return chain.from_it...
Get the indem>x m> of the object inside an array, matching a condition
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As of 2016, you're supposed to use Array.findIndem>x m> (an ES2015/ES6 standard) for this:
a = [
{prop1:"abc",prop2:"qwe"},
{prop1:"bnmb",prop2:"yutu"},
{prop1:"zm>x m>vz",prop2:"qwrq"}];
indem>x m> = a.findIndem>x m>(m>x m> => m>x m>.prop2 ==="yutu");
console.log(indem>x m>);
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How can I trim leading and trailing white space?
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# Returns string without leading white space
trim.leading <- function (m>x m>) sub("^\\s+", "", m>x m>)
# Returns string without trailing white space
trim.trailing <- function (m>x m>) sub("\\s+$", "", m>x m>)
# Returns string without leading or trailing white space
trim <- function (m>x m>) gsub("^\\s+|\\s+$",...
How do I perform an IF…THEN in an SQL SELECT?
...aultcase>
END AS <newcolumnname>
FROM <table>
The em>x m>tended case:
SELECT CASE WHEN <test> THEN <returnvalue>
WHEN <othertest> THEN <returnthis>
ELSE <returndefaultcase>
END AS <newcolumnname...
How to validate an email address in JavaScript
Is there a regular em>x m>pression to validate an email address in JavaScript?
95 Answers
9...
Can you Run m>X m>code in Linum>x m>?
Can you run m>X m>code in Linum>x m>? Mac OS m>X m> was based on BSD Unim>x m>, so is it possible?
13 Answers
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How to select the row with the mam>x m>imum value in each group
...iple observations for each subject I want to take a subset with only the mam>x m>imum data value for each record. For em>x m>ample, with a following dataset:
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Drawing a line/path on Google Maps
...otected boolean isRouteDisplayed() {
return false;
}
class MyOverlay em>x m>tends Overlay{
public MyOverlay(){
}
public void draw(Canvas canvas, MapView mapv, boolean shadow){
super.draw(canvas, mapv, shadow);
Paint mPaint = new Paint();
mPaint.setDither(...
Precision String Format Specifier In Swift
...est solution so far, following from David's response:
import Foundation
em>x m>tension Int {
func format(f: String) -> String {
return String(format: "%\(f)d", self)
}
}
em>x m>tension Double {
func format(f: String) -> String {
return String(format: "%\(f)f", self)
}
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Is it possible to override JavaScript's toString() function to provide meaningful output for debuggi
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You can override toString in Javascript as well. See em>x m>ample:
function Foo() {}
// toString override added to prototype of Foo class
Foo.prototype.toString = function() {
return "[object Foo]";
}
var f = new Foo();
console.log("" + f); // console displays [object Foo]
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