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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 do I conditionally apply CSS styles in AngularJS?
...ange dynamically. Think programmable control of the style values.
ng-show and ng-hide - use if you only need to show or hide something (modifies CSS)
ng-if - new in version 1.1.5, use instead of the more verbose ng-switch if you only need to check for a single condition (modifies DOM)
ng-switch - u...
How to remove element from array in forEach loop?
... element in an array in a forEach loop, but am having trouble with the standard solutions I've seen.
7 Answers
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How does Dijkstra's Algorithm and A-Star compare?
...was looking at what the guys in the Mario AI Competition have been doing and some of them have built some pretty neat Mario bots utilizing the A* (A-Star) Pathing Algorithm.
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How do I find the width & height of a terminal window?
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echo -e "lines\ncols"|tput -S to get both the lines and cols see: linux.about.com/library/cmd/blcmdl1_tput.htm
– nickl-
Jan 26 '13 at 3:49
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Which UUID version to use?
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Version 1: This generates a unique ID based on a network card MAC address and a timer. These IDs are easy to predict (given one, I might be able to guess another one) and can be traced back to your network card. It's not recommended to create these.
Version 4: These are generated from random (or ps...
What is the difference between svg's x and dx attribute?
What is the difference between svg's x and dx attribute (or y and dy)? When would be a proper time to use the axis shift attribute (dx) versus the location attribute (x)?
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How to increase font size in the Xcode editor?
... match the mindset of software engineers that make 100+ character variable and method names. Enough of my complaining)
I'll modify a previous post for the current version.
Close any projects you have open in Xcode (Otherwise the Font window will be inaccessible while a project is open.)
Go to XCo...
rails 3.1.0 ActionView::Template::Error (application.css isn't precompiled)
...de a basic rails app with a simple pages controller with an index function and when I load the page I get:
14 Answers
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Why does jQuery or a DOM method such as getElementById not find the element?
...ers parse HTML documents from top to bottom. Elements are added to the DOM and scripts are (generally) executed as they're encountered. This means that order matters. Typically, scripts can't find elements which appear later in the markup because those elements have yet to be added to the DOM.
Cons...