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Transpose a data frame
...
You can use the transpose function from the data.table library. Simple and fast solution that keeps numeric values as numeric.
library(data.table)
# get data
data("mtcars")
# transpose
t_mtcars <- transpose(mtcars)
# get row and colnames in order
...
Comparing Timer with DispatcherTimer
...er high, until I corrected it with this: timer1.Interval = System.TimeSpan.FromSeconds(1);
– Lonnie Best
Feb 15 '10 at 0:45
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show 2 more co...
How to pipe input to a Bash while loop and preserve variables after loop ends
...he { ... }. You mention this in the question. AFAIK, you can do a return from within these inside a function.
Bash also provides the shopt builtin and one of its many options is:
lastpipe
If set, and job control is not active, the shell runs the last command of a pipeline not executed in the bac...
How to detect the swipe left or Right in Android?
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I like the code from @user2999943. But just some minor changes for my own purposes.
@Override
public boolean onTouchEvent(MotionEvent event)
{
switch(event.getAction())
{
case MotionEvent.ACTION_DOWN:
x1 = event...
Is there a performance gain in using single quotes vs double quotes in ruby?
...n. But you only get the performance hit if you actually do that.
Modified from Zetetic's example:
require 'benchmark'
n = 1000000
Benchmark.bm do |x|
x.report("assign single") { n.times do; c = 'a string'; end}
x.report("assign double") { n.times do; c = "a string"; end}
x.report("assign int...
Is there a difference between foreach and map?
...following code:-
Here I've simply assigned the result of the return value from the map and forEach methods.
var arr = [1, 2, 3, 4, 5];
var ar1 = arr.map(function(val, ind, arr){
console.log("arr[" + ind + "]: " + Math.pow(val,2));
return val;
});
console.log();
console.log(ar1);
console....
How can I add a boolean value to a NSDictionary?
...number... methods that take booleans, just as it does integers and so on.
From the NSNumber class reference:
// Creates and returns an NSNumber object containing a
// given value, treating it as a BOOL.
+ (NSNumber *)numberWithBool:(BOOL)value
and:
// Returns an NSNumber object initialized to ...
Moving average or running mean
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@denfromufa, I believe the documentation covers the implementation well enough, and it also links to Wikipedia which explains the maths. Considering the focus of the question, do you think this answer needs to copy those?
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What blocks Ruby, Python to get Javascript V8 speed? [closed]
..., not a JIT).
Many also feel that Ruby and Python could benefit immensely from removing their respective global interpreter locks.
You also have to understand that Python and Ruby are both much heavier languages than JS -- they provide far more in the way of standard library, language features, an...
What is the difference between ~> and >= when specifying rubygem in Gemfile?
...t, and how to upload it so that others can install it.
How to create a Gem from scratch with Bundler
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