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Can dplyr package be used for conditional mutating?
...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 na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
How do I output coloured text to a Linux terminal?
...
You need to output ANSI colour codes. Note that not all terminals support this; if colour sequences are not supported, garbage will show up.
Example:
cout << "\033[1;31mbold red text\033[0m\n";
Here, \033 is the ESC character, ASCII 27. It is followed by [, then zero o...
Python dictionary: Get list of values for list of keys
...n list-comp:
Build list and throw exception if key not found: map(mydict.__getitem__, mykeys)
Build list with None if key not found: map(mydict.get, mykeys)
Alternatively, using operator.itemgetter can return a tuple:
from operator import itemgetter
myvalues = itemgetter(*mykeys)(mydict)
# use ...
How do I output an ISO 8601 formatted string in JavaScript?
...
There is already a function called toISOString():
var date = new Date();
date.toISOString(); //"2011-12-19T15:28:46.493Z"
If, somehow, you're on a browser that doesn't support it, I've got you covered:
if ( !Date.prototype.toISOString ) {
( functi...
React.js: onChange event for contentEditable
...hich fixes a bug in my implementation.
Use the onInput event, and optionally onBlur as a fallback. You might want to save the previous contents to prevent sending extra events.
I'd personally have this as my render function.
var handleChange = function(event){
this.setState({html: event.ta...
Getting the class name from a static method in Java
...tatic context to mean the current Class in Java, that that "class.xxx" was allowed in either instance or static code to mean this class! The problem with this is that MyClass is verbose and redundant, in the context. But then as much as I like Java it does seem to lean towards verbosity.
...
Where do I set my company name?
...lt, Xcode inserts a company
name something similar to the
following in all new source files (.m
.h etc):
Copyright (c) 2009 MyCompanyName. All
rights reserved.
Changing this reference is as simple
as entering the following from within
a terminal window, replacing
“YourNameH...
jQuery get values of checked checkboxes into array
I am trying to get values of all checkboxes that are currently checked and store them into an array. Here is my code so far:
...
Captured variable in a loop in C#
...ompiler is generating a class that represents the closure for your method call. It uses that single instance of the closure class for each iteration of the loop. The code looks something like this, which makes it easier to see why the bug happens:
void Main()
{
List<Func<int>> actio...
How to make a Java Generic method static?
...urn value always introduce (declare) a new generic type variable.
Additionally, type variables between types (ArrayUtils) and static methods (appendToArray) never interfere with each other.
So, what does this mean:
In my answer <E> would hide the E from ArrayUtils<E> if the method woul...