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On localhost, how do I pick a free port number?
...do I figure out which port is available? I assume I cannot listen on port 80 or 21?
5 Answers
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How to use hex color values
...f, green ff and blue ff. You can write hexadecimal notation in Swift using 0x prefix, e.g 0xFF
To simplify the conversion, let's create an initializer that takes integer (0 - 255) values:
extension UIColor {
convenience init(red: Int, green: Int, blue: Int) {
assert(red >= 0 &&amp...
Best way to test if a row exists in a MySQL table
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edited Sep 4 '19 at 19:20
SovietFrontier
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answered Nov 4 '09 ...
Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
...le(a = c(1, 2), b = c(11, 12))
newDT <- DT
.Internal(inspect(DT))
# @0000000003B7E2A0 19 VECSXP g0c7 [OBJ,NAM(2),ATT] (len=2, tl=100)
# @00000000040C2288 14 REALSXP g0c2 [NAM(2)] (len=2, tl=0) 1,2
# @00000000040C2250 14 REALSXP g0c2 [NAM(2)] (len=2, tl=0) 11,12
# ATTRIB: # ..snip..
.Inte...
Formatting a number with exactly two decimals in JavaScript
...ich rounds my numbers to two decimal places. But I get numbers like this: 10.8, 2.4, etc. These are not my idea of two decimal places so how I can improve the following?
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Replacing NAs with latest non-NA value
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divibisan
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answered Oct 12 '11 at 5:32
Dirk EddelbuettelDir...
List comprehension on a nested list?
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answered Aug 6 '13 at 6:05
Andrew ClarkAndrew Clark
171k2525 gold badges236236 silver badges278278 bronze badges
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How can I update the current line in a C# Windows Console App?
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805
If you print only "\r" to the console the cursor goes back to the beginning of the current line...
Difference between variable declaration syntaxes in Javascript (including global variables)?
...al terms they're not usually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1.1 (new with ES2015)
const a = 0; // 1.2 (new wit...
How to check if a string “StartsWith” another string?
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answered Mar 14 '09 at 20:19
Christian C. SalvadóChristian C. Salvadó
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