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How to get first and last day of previous month (with timestamp) in SQL Server
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13 Answers
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Split a vector into chunks in R
... is seq_along(), split() and ceiling():
> d <- rpois(73,5)
> d
[1] 3 1 11 4 1 2 3 2 4 10 10 2 7 4 6 6 2 1 1 2 3 8 3 10 7 4
[27] 3 4 4 1 1 7 2 4 6 0 5 7 4 6 8 4 7 12 4 6 8 4 2 7 6 5
[53] 4 5 4 5 5 8 7 7 7 6 2 4 3 3 8 11 6 6 1...
How to group dataframe rows into list in pandas groupby?
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12 Answers
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Understanding how recursive functions work
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18 Answers
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What is the best regular expression to check if a string is a valid URL?
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Index all *except* one item in python
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115
For a list, you could use a list comp. For example, to make b a copy of a without the 3rd ele...
What is the syntax to insert one list into another list in python?
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Do you mean append?
>>> x = [1,2,3]
>>> y = [4,5,6]
>>> x.append(y)
>>> x
[1, 2, 3, [4, 5, 6]]
Or merge?
>>> x = [1,2,3]
>>> y = [4,5,6]
>>> x + y
[1, 2, 3, 4, 5, 6]
>>> x.extend(y)
>&g...
How can I plot with 2 different y-axes?
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127
update: Copied material that was on the R wiki at http://rwiki.sciviews.org/doku.php?id=tips:g...
Can dplyr package be used for conditional mutating?
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Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with i...
Most popular screen sizes/resolutions on Android phones [closed]
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You can see the resolutions for those categories in the Table 2, in this section: http://develop...