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How can you hide database output in Rails console?
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Soviut
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answered Jul 16 '13 at 11:53
Aaron B. Russel...
`levels
...tion, @Marek posted the following solution:
https://stackoverflow.com/a/10432263/636656
4 Answers
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Slicing of a NumPy 2d array, or how do I extract an mxm submatrix from an nxn array (n>m)?
...mns), making it a new, mxm array. For this example let us say the array is 4x4 and I want to extract a 2x2 array from it.
7...
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] + ') ' + ...
Finding the index of elements based on a condition using python list comprehension
... Mike GrahamMike Graham
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2
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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...
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...