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Reasons for using the set.seed function
...produce as I just asked for something "random":
R> sample(LETTERS, 5)
[1] "K" "N" "R" "Z" "G"
R> sample(LETTERS, 5)
[1] "L" "P" "J" "E" "D"
These two, however, are identical because I set the seed:
R> set.seed(42); sample(LETTERS, 5)
[1] "X" "Z" "G" "T" "O"
R> set.seed(42); sample(LE...
How do I list all files of a directory?
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21 Answers
21
Active
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SQLite table constraint - unique on multiple columns
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edited May 18 at 7:31
Martin Tournoij
22.1k1717 gold badges8585 silver badges116116 bronze badges
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Regex to match any character including new lines
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201
Add the s modifier to your regex to cause . to match newlines:
$string =~ /(START)(.+?)(END)/s;...
TypeError: module.__init__() takes at most 2 arguments (3 given)
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edited Jan 17 '18 at 10:14
Aran-Fey
27.5k55 gold badges6666 silver badges107107 bronze badges
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typecast string to integer - Postgres
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129
Wild guess: If your value is an empty string, you can use NULLIF to replace it for a NULL:
SE...
How can I extract a predetermined range of lines from a text file on Unix?
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sed -n '16224,16482p;16483q' filename > newfile
From the sed manual:
p -
Print out the pattern space (to the standard output). This command is usually only used in conjunction with the -n command-line option.
n -...
Django database query: How to get object by id?
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186
If you want to get an object, using get() is more straightforward:
obj = Class.objects.get(pk...
How to show vertical line to wrap the line in Vim?
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16
Edit: For Vim >=7.3 see answer below.
Unfortunately vim has no mechanism to display a verti...