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What are all the uses of an underscore in Scala?
...ses of the underscore is Scala _ [underscore] magic.
Examples:
def matchTest(x: Int): String = x match {
case 1 => "one"
case 2 => "two"
case _ => "anything other than one and two"
}
expr match {
case List(1,_,_) => " a list with three element and the first elem...
How to append rows to an R data frame
....frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n), y = character(n), stringsAsFactors = FALSE)
for(i in 1:n){
df$x[i] <- i
df$y[i] <- toString(i)
...
Best way to combine two or more byte arrays in C#
...econds
I increased the size of each array to 100 elements and re-ran the test:
New Byte Array using System.Array.Copy - 0.2812554 seconds
New Byte Array using System.Buffer.BlockCopy - 0.2500048 seconds
IEnumerable<byte> using C# yield operator - 0.0625012 seconds
IEnumerable<...
How to configure logging to syslog in Python?
...erything to syslog. After reading documentation I came up with this simple test script:
11 Answers
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How do I compare two string variables in an 'if' statement in Bash? [duplicate]
...ngimed, [ is a command (actually, an alternate name for the command called test); if you run which [, you'll see there's actually an executable file for it on disk (even though the shell may provide a built-in implementation as a performance optimization). Just like you have to put a space between t...
Test parameterization in xUnit.net similar to NUnit
...
xUnit offers a way to run parameterized tests through something called data theories. The concept is equivalent to the one found in NUnit but the functionality you get out of the box is not as complete.
Here's an example:
[Theory]
[InlineData("Foo")]
[InlineData(...
How do I check to see if a value is an integer in MySQL?
...XP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just test for
ceil(field) = field
instead.
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Why does make think the target is up to date?
...
Maybe you have a file/directory named test in the directory. If this directory exists, and has no dependencies that are more recent, then this target is not rebuild.
To force rebuild on these kind of not-file-related targets, you should make them phony as follow...
Executing multiple commands from a Windows cmd script
... I was trying to do something similar with npm updates and protractor tests. I didn't think this answer applied to me until I realized npm and protractor are .cmd files on Windows.
– joshden
Apr 20 '17 at 20:32
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How to test multiple variables against a value?
...wn (False if 0, True otherwise).
You can shorten that using a containment test against a tuple:
if 1 in (x, y, z):
or better still:
if 1 in {x, y, z}:
using a set to take advantage of the constant-cost membership test (in takes a fixed amount of time whatever the left-hand operand is).
When ...