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Subset of rows containing NA (missing) values in a chosen column of a data frame
...ated. THe point is to use is.na, I wrongly interpreted you wanted to check all variables.
– Joris Meys
Nov 2 '11 at 21:34
3
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What are the differences between double-dot “..” and triple-dot “…” in Git commit ranges?
...t
can be written as "r1..r2".
A similar notation "r1...r2" is
called symmetric difference of r1 and
r2 and is defined as "r1 r2 --not
$(git merge-base --all r1 r2)". It is
the set of commits that are
reachable from either one of r1 or r2
but not from both.
Which basical...
var functionName = function() {} vs function functionName() {}
...);
function functionTwo() {
console.log("Hello!");
}
Historically, function declarations defined within blocks were handled inconsistently between browsers. Strict mode (introduced in ES5) resolved this by scoping function declarations to their enclosing block.
'use strict';
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What is the difference between integration and unit tests?
I know the so-called textbook definition of unit tests and integration tests. What I am curious about is when it is time to write unit tests... I will write them to cover as many sets of classes as possible.
...
How to disable text selection highlighting
... a CSS standard way to disable the highlighting effect if the user accidentally selects the text?
48 Answers
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How would Git handle a SHA-1 collision on a blob?
...ase. This is with version 2.7.9~rc0+next.20151210 (Debian version). I basically just reduced the hash size from 160-bit to 4-bit by applying the following diff and rebuilding git:
--- git-2.7.0~rc0+next.20151210.orig/block-sha1/sha1.c
+++ git-2.7.0~rc0+next.20151210/block-sha1/sha1.c
@@ -246,6 +246...
Is D a credible alternative to Java and C++? [closed]
...of a programming language for real-world software development is only partially related to the quality of the language itself. As a pure language, D arguably has many advantages over C++ and Java. At the very least it is a credible alternative as a pure language, all other things being equal.
How...
Remove empty elements from an array in Javascript
...ll return you a new array with the elements that pass the criteria of the callback function you provide to it.
For example, if you want to remove null or undefined values:
var array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,];
var filtered = array.filter(function (el) {
...
Best way to load module/class from lib folder in Rails 3?
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# Autoload lib/ folder including all subdirectories
config.autoload_paths += Dir["#{config.root}/lib/**/"]
Source: Rails 3 Quicktip: Autoload lib directory including all subdirectories, avoid lazy loading
Please mind that files contained in the lib folder...
How to do a https request with bad certificate?
Say I want to get https://golang.org programatically. Currently golang.org (ssl) has a bad certificate which is issued to *.appspot.com So when I run this:
...