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Can dplyr package be used for conditional mutating?
... TRUE ~ NA_real_))
Added - arithmetic/na_if If the values are numeric and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using...
How to apply specific CSS rules to Chrome only?
...rom https://jeffclayton.wordpress.com/2015/08/10/1279/
/* Chrome, Safari, AND NOW ALSO the Edge Browser and Firefox */
@media and (-webkit-min-device-pixel-ratio:0) {
div{top:10;}
}
/* Chrome 29+ */
@media screen and (-webkit-min-device-pixel-ratio:0)
and (min-resolution:.001dpcm) {
div{t...
PHP Function Comments
...net/license/3_01.txt. If you did not receive a copy of
* the PHP License and are unable to obtain it through the web, please
* send a note to license@php.net so we can mail you a copy immediately.
*
* @category CategoryName
* @package PackageName
* @author Original Author <author@...
Javascript Functions and default parameters, not working in IE and Chrome
...u can't do this, but you can instead do something like:
function saveItem(andClose) {
if(andClose === undefined) {
andClose = false;
}
}
This is often shortened to something like:
function setName(name) {
name = name || 'Bob';
}
Update
The above is true for ECMAScript <= 5. E...
Add support library to Android Studio project
I just installed the new Android Studio and I'm looking for a way to import the support library for Android.
6 Answers
...
How efficient can Meteor be while sharing a huge collection among many clients?
...iption provides; the Mongo driver, which watches the
database for changes; and the merge box, which combines all of a
client's active subscriptions and sends them out over the network to the
client.
Publish functions
Each time a Meteor client subscribes to a collection, the server runs a
publish f...
OS X Terminal Colors [closed]
...rminal colors.
Edit your .bash_profile (since OS X 10.8) — or (for 10.7 and earlier): .profile or .bashrc or /etc/profile (depending on availability) — in your home directory and add following code:
export CLICOLOR=1
export LSCOLORS=GxFxCxDxBxegedabagaced
CLICOLOR=1 simply enables coloring o...
What are all the user accounts for IIS/ASP.NET and how do they differ?
...with ASP.NET 4.0 installed there is a whole slew of related user accounts, and I can't understand which one is which, how to they differ, and which one is REALLY the one that my app runs under. Here's a list:
...
How to install GCC piece by piece with GMP, MPFR, MPC, ELF, without shared libraries?
...s of dependencies, not using a package manager (like yum, rpm, apt, dpkg), and not using shared libraries?
6 Answers
...
Dashed line border around UIView
...
You can set the border with this pattern using Layer and Bezier path like below examples.
Objective-C
CAShapeLayer *yourViewBorder = [CAShapeLayer layer];
yourViewBorder.strokeColor = [UIColor blackColor].CGColor;
yourViewBorder.fillColor = nil;
yourViewBorder.lineDashPattern...