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How to get a substring of text?
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answered May 31 '11 at 8:14
Matteo AlessaniMatteo Alessani
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Ruby/Rails: converting a Date to a UNIX timestamp
...xample:
>> Date.new(2009,11,26).to_time
=> Thu Nov 26 00:00:00 -0800 2009
>> Date.new(2009,11,26).to_time.to_i
=> 1259222400
>> Time.at(1259222400)
=> Thu Nov 26 00:00:00 -0800 2009
Note that the intermediate DateTime object is in local time, so the timestamp might be a...
Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
...r necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3 5
9: a 6 6
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Where is JAVA_HOME on macOS Mojave (10.14) to Lion (10.7)?
...exec/java_home -v 1.7)"
or
export JAVA_HOME="$(/usr/libexec/java_home -v 1.8)"
Update: added -v flag based on Jilles van Gurp response.
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How to get svn remote repository URL?
...1-13 16:43:13 -0600 (Mon, 13 Jan 2003)
Text Last Updated: 2003-01-16 21:18:16 -0600 (Thu, 16 Jan 2003)
Properties Last Updated: 2003-01-13 21:50:19 -0600 (Mon, 13 Jan 2003)
Checksum: d6aeb60b0662ccceb6bce4bac344cb66
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What's the standard way to work with dates and times in Scala? Should I use Java types or there are
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From Java SE 8 onwards, users are asked to migrate to java.time (JSR-310). There are efforts on creating scala libraries wrapping java.time for scala such as scala-time. If targeting lower than SE 8 use one of the below. Also see Why JSR...
Comma separator for numbers in R?
...tor of characters. I'd only use that for printing.
> prettyNum(12345.678,big.mark=",",scientific=FALSE)
[1] "12,345.68"
> format(12345.678,big.mark=",",scientific=FALSE)
[1] "12,345.68"
EDIT: As Michael Chirico says in the comment:
Be aware that these have the side effect of padding the ...
Sorting 1 million 8-decimal-digit numbers with 1 MB of RAM
... 1 MB of RAM and no other local storage. I must use it to accept 1 million 8-digit decimal numbers over a TCP connection, sort them, and then send the sorted list out over another TCP connection.
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Timeout command on Mac OS X?
... kvzkvz
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MySQL select where column is not empty
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Compare value of phone2 with empty string:
select phone, phone2
from jewishyellow.users
wher...