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Remove duplicated rows using dplyr

...ction for this purpose. Original answer below: library(dplyr) set.seed(123) df <- data.frame( x = sample(0:1, 10, replace = T), y = sample(0:1, 10, replace = T), z = 1:10 ) One approach would be to group, and then only keep the first row: df %>% group_by(x, y) %>% filter(row_nu...
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what is faster: in_array or isset? [closed]

...e, you can check out the compiled version of your script: echo isset($arr[123]) compiled vars: !0 = $arr line # * op fetch ext return operands ----------------------------------------------------------------------------- 1 0 > ZEND_ISSET_ISEMPTY_...
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What is “export default” in javascript?

...ello() { console.log("Modul: Saying hello!"); } export let variable = 123; modul2.js export function hello2() { console.log("Module2: Saying hello for the second time!"); } export let variable2 = 456; modul3.js export default function hello3() { console.log("Module3: Saying hello...
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Several ports (8005, 8080, 8009) required by Tomcat Server at localhost are already in use

...st gives me the help for the kill command. – CoderGuy123 Jun 1 '15 at 2:18 ...
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Why can't variable names start with numbers?

... If it had to be numbers+alpha, then you could still do String 0x123 = "Hello World". Unless you state that variable names are "numbers+alpha that don't parse to a valid numeric designation", and that's just silly. – eaolson Oct 11 '09 at 3:56 ...
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Preferred order of writing latitude & longitude tuples in GIS services

.... For example, my hometown of Eugene, Oregon is at approximately N 44.1, W 123.1. If in maps.google.com I enter 44.1 -123.1, it goes to Eugene. If I enter -123.1 44, it tells me it can't find it. Interestingly, though, if I enter 123.1 W 44 N, it figures it out and goes to Eugene, so there is some f...
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Getting parts of a URL (Regex)

...ex: var a = document.createElement('a'); a.href = 'http://www.example.com:123/foo/bar.html?fox=trot#foo'; ['href','protocol','host','hostname','port','pathname','search','hash'].forEach(function(k) { console.log(k+':', a[k]); }); /*//Output: href: http://www.example.com:123/foo/bar.html?fox=t...
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Cache busting via params

... The param ?v=1.123 indicates a query string, and the browser will therefore think it is a new path from, say, ?v=1.0. Thus causing it to load from file, not from cache. As you want. And, the browser will assume that the source will stay t...
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How to remove the hash from window.location (URL) with JavaScript without page refresh?

... This will remove the trailing hash as well. eg: http://test.com/123#abc -> http://test.com/123 if(window.history.pushState) { window.history.pushState('', '/', window.location.pathname) } else { window.location.hash = ''; } ...
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How to hide the “back” button in UINavigationController?

...nswered Dec 11 '13 at 8:02 mattv123mattv123 89988 silver badges1313 bronze badges ...