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Group by multiple columns in dplyr, using string vector input
...= names(data)[-3]
library(dplyr)
df1 <- data %>%
group_by_at(vars(one_of(columns))) %>%
summarize(Value = mean(value))
#compare plyr for reference
df2 <- plyr::ddply(data, columns, plyr::summarize, value=mean(value))
table(df1 == df2, useNA = 'ifany')
## TRUE
## 27
The output ...
How can I print a circular structure in a JSON-like format?
... In the following case, a value is discarded:
var a = {b:1}
var o = {};
o.one = a;
o.two = a;
// one and two point to the same object, but two is discarded:
JSON.stringify(o, ...);
But the concept stands: Use a custom replacer, and keep track of the parsed object values.
As a utility function wr...
Parse error: Syntax error, unexpected end of file in my PHP code
...not (or rather fcgi does not) so if your stumped by why this is working on one web server and not another you know why
– Sammaye
Jul 18 '14 at 13:53
...
Google Chrome Printing Page Breaks
...ng the problem for me. Not sure why a br doesn't work and a div does, but nonetheless an easy change.
– Jeff Davis
Mar 30 '11 at 21:37
...
Where is the “Create Unit Tests” selection?
...2015 blogs.msdn.com/b/visualstudioalm/archive/2015/03/06/… thanks to the ones that voted for it in visualstudio.uservoice.com/forums/121579-visual-studio/… . @furier : Maybe you voted for it?
– LosManos
Mar 11 '15 at 11:45
...
Abandoning changes without deleting from history
... want to work with branches at this stage, but that's exactly what you've done. When you went back to an earlier version and committed something that worked you created a branch - an unnamed branch, but a branch all the same.
There's no problem with just carrying on just as you are and not worryi...
How to change background color in android app
... This is the right answer because it has themes, I believe. A one-liner is NOT the simplest way, but a way to spread an entire style to everything is. Styles are how you achieve one-line with even complex changes. Also, styles work on preferences, unlike general attributes. (although st...
How can I disable ARC for a single file in a project?
...e 4, in build phases, and compile sources, there are actually two columns. One for the file name, and another for the compile flags for that one file. This is where you enter this specific compiler flag.
– casademora
Jul 26 '11 at 17:58
...
Sequelize.js delete query?
...
For anyone using Sequelize version 3 and above, use:
Model.destroy({
where: {
// criteria
}
})
Sequelize Documentation - Sequelize Tutorial
...
Where to place JavaScript in an HTML file?
...cripts at the bottom of your page because of the way browsers download components.
Of course Levi's comment "just before you need it and no sooner" is really the correct answer, i.e. "it depends".
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