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What is a regular expression for a MAC Address?
... @pilcrow could you please explain why this mac: C8:FD:19:55:E6:3A fails? It's an actual mac address. I modified your regex to accept : only /^(?:[[:xdigit:]]{2}([:]))(?:[[:xdigit:]]{2}\1){4}[[:xdigit:]]{2}$/ Thanks!
– Sam
May 27 '19 at 15:37
...
Fastest way to find second (third…) highest/lowest value in vector or column
...746.7627 1433.221 1500.7865 13768.148 100
For 1 million numbers:
N = 1e6 #evaluates to 1 million
x = rnorm(N)
microbenchmark::microbenchmark(
Rfast = Rfast::nth(x,5,descending = T),
maxN = maxN(x,5),
order = x[order(x, decreasing = T)[5]]
)
Unit: milliseconds
expr min ...
What does .SD stand for in data.table in R
...ttps://sashat.me/2017/01/11/list-of-20-simple-distinct-colors/
col16 = c('#e6194b', '#3cb44b', '#ffe119', '#0082c8', '#f58231', '#911eb4',
'#46f0f0', '#f032e6', '#d2f53c', '#fabebe', '#008080', '#e6beff',
'#aa6e28', '#fffac8', '#800000', '#aaffc3')
par(oma = c(2, 0, 0, 0))
sappl...
How do I parse a string to a float or int?
...erything with spaces in between cannot be converted, like "- 12.3" and "45 e6"
– Simon
Aug 12 '19 at 13:43
...
How can I reconcile detached HEAD with master/origin?
...git rev-parse refs/heads/master yield 17a02998078923f2d62811326d130de991d1a95a
That commit is the current tip or “head” of the master branch.
git rev-parse HEAD also yields 17a02998078923f2d62811326d130de991d1a95a
This is what it means to be a “symbolic ref”. It points to an object through s...
How to compare two floating point numbers in Bash?
... scientific format, provided a capital letter E is employed, e.g. num1=3.44E6
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Replace a value if null or undefined in JavaScript
...lter1 = "abc"
// filter2 = "Smith"
More Detailed Tutorial
Browser Support 92% July 2020
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Setting up a deployment / build / CI cycle for PHP projects
... community wiki
4 revs, 3 users 92%Steen
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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
... answered Apr 7 '19 at 0:43
cs95cs95
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pandas GroupBy columns with NaN (missing) values
... answered May 20 at 21:10
cs95cs95
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