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Finding the index of elements based on a condition using python list comprehension
... Mike GrahamMike Graham
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What does .SD stand for in data.table in R
...,3), v=1:6)
setkey(DT, y)
DT
# x y v
# 1: a 1 1
# 2: b 1 3
# 3: c 1 5
# 4: a 3 2
# 5: b 3 4
# 6: c 3 6
Doing this may help you see what .SD is:
DT[ , .SD[ , paste(x, v, sep="", collapse="_")], by=y]
# y V1
# 1: 1 a1_b3_c5
# 2: 3 a2_b4_c6
Basically, the by=y statement breaks the orig...
Regular Expression to reformat a US phone number in Javascript
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Assuming you want the format "(123) 456-7890":
function formatPhoneNumber(phoneNumberString) {
var cleaned = ('' + phoneNumberString).replace(/\D/g, '')
var match = cleaned.match(/^(\d{3})(\d{3})(\d{4})$/)
if (match) {
return '(' + match[1] + ') ' + ...
Difference between . and : in Lua
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242
The colon is for implementing methods that pass self as the first parameter. So x:bar(3,4)shou...
dplyr: “Error in n(): function should not be called directly”
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edited Jan 27 '15 at 0:44
Michael Bellhouse
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an...
How do I specify different Layouts in the ASP.NET MVC 3 razor ViewStart file?
...itrov
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Change the name of the :id parameter in Routing resources for Rails
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194
Rails 4 & 5
In Rails 4, the :param option was added, which seems to do exactly what you're ...
Convert NSData to String?
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Max MacLeod
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answered Jun 21 '11 at 16:11
louiscoquioloui...
How to make unicode string with python3
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IanS
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answered Jul 25 '11 at 5:21
John La RooyJohn La Ro...