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How to sort a dataframe by multiple column(s)
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You can use the order() function directly without resorting to add-on tools -- see this simpler answer which uses a trick right from the top of the example(order) code:
R> dd[with(dd, order(-z, b)), ]
b x y z
4 Low C 9 2
2 Med D 3 1
1 Hi A ...
Best ways to teach a beginner to program? [closed]
... helps.
1) FizzBuzz. Start with command line programs. You can write some fun games, or tools, very quickly, and you learn all of the language features very quickly without having to learn the GUI tools first. These early apps should be simple enough that you won't need to use any real debugging to...
EProgrammerNotFound exception in Delphi?
...mon errors with a similar message. Internally we've always joked and poked fun at different things and people (mostly on the team itself). If you don't have a sense of humor, you're destined to an early grave.
It was a simple conversation;
"Oh, you should have raised the EProgrammerNotFound excep...
Remove substring from the string
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ruby is fun! really enjoy seeing stuff like: asdf['bar'] = ''
– Peter Butkovic
Dec 2 '14 at 10:11
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Block Comments in Clojure
...re!"))
Check me out!
)
Just wrap your comments in (comment ..) :)
Have fun!
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Function to clear the console in R and RStudio
I am wondering if there is a function to clear the console in R and, in particular, RStudio I am looking for a function that I can type into the console, and not a keyboard shortcut.
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Google Maps V3 - How to calculate the zoom level for a given bounds
... longitude, and then take the smaller (further out) of the two.
Here is a function that uses both latitude and longitude:
function getBoundsZoomLevel(bounds, mapDim) {
var WORLD_DIM = { height: 256, width: 256 };
var ZOOM_MAX = 21;
function latRad(lat) {
var sin = Math.sin(lat...
Split comma-separated strings in a column into separate rows
..., "B", "B", "B", "B", "A")
library(data.table)
library(magrittr)
Define function for benchmark runs of problem size n
run_mb <- function(n) {
# compute number of benchmark runs depending on problem size `n`
mb_times <- scales::squish(10000L / n , c(3L, 100L))
cat(n, " ", mb_times, "...
Check if application is installed - Android
...pp")
and the call the following method to check if the app is installed
fun isInstalled(intent:Intent) :Boolean{
val list = context.packageManager.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY)
return list.isNotEmpty()
}
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How to convert String to Long in Kotlin?
...dix] is not a valid radix for string to number conversion.
public inline fun String.toLong(radix: Int): Long = java.lang.Long.parseLong(this, checkRadix(radix))
4. string.toLongOrNull(10)
Parses the string as a [Long] number and returns the result or null
if the string is not a valid repre...