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Repeat each row of data.frame the number of times specified in a column
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175
Here's one solution:
df.expanded <- df[rep(row.names(df), df$freq), 1:2]
Result:
var1...
Sort an array in Java
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edited Jan 22 '12 at 10:55
answered Jan 20 '12 at 7:56
Pe...
Using LIMIT within GROUP BY to get N results per group?
...-----------------------
| p01 | 2006,2003,2008,2001,2007,2009,2002,2004,2005,2000 |
| p02 | 2001,2004,2002,2003,2000,2006,2007 |
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And then you could use FIND_IN_SET, that returns the position of the first argument inside the...
Sorting a tab delimited file
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315
Using bash, this will do the trick:
$ sort -t$'\t' -k3 -nr file.txt
Notice the dollar sign in...
How to handle exceptions in a list comprehensions?
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– Nathan Fellman
Oct 6 '09 at 22:15
9
I do not see "not using list comprehensions" as a part of...
Is object empty? [duplicate]
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457
I'm assuming that by empty you mean "has no properties of its own".
// Speed up calls to hasOw...
find -exec with multiple commands
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answered May 18 '11 at 11:25
TinkerTinker
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Get the real width and height of an image with JavaScript? (in Safari/Chrome)
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358
Webkit browsers set the height and width property after the image is loaded. Instead of using ...
SSL Error When installing rubygems, Unable to pull data from 'https://rubygems.org/
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Find path for certificate:
cert_file=$(ruby -ropenssl -e 'puts OpenSSL::X509::DEFAULT_CERT_FILE')
Generate certificate:
security find-certificate -a -p /Library/Keychains/System.keychain > "$cert_file"
security find-certificate -a -p /System/Library/Keychains/SystemRootCertificates.keychain ...
Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?
...reasons, has been lifted in recent versions of MySQL:
Changes in MySQL 5.6.5 (2012-04-10, Milestone 8)
Previously, at most one TIMESTAMP column per table could be
automatically initialized or updated to the current date and time.
This restriction has been lifted. Any TIMESTAMP column d...