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Remove duplicated rows using dplyr
... @hadley I like the unique() and distinct() function, however, they all remove the 2nd duplicate from the data frame. what if I want to have all 1st encounters of the duplicate value removed? How could this be done? Thanks for any help!
– FlyingDutch
Feb...
How to get a property value based on the name
....Name == propertyName)
.GetValue(car, null);
}
If you want to be really fancy, you could make it an extension method:
public static object GetPropertyValue(this object car, string propertyName)
{
return car.GetType().GetProperties()
.Single(pi => pi.Name == propertyName)
....
How do you run a crontab in Cygwin on Windows?
...
You need to also install cygrunsrv so you can set cron up as a windows service, then run cron-config.
If you want the cron jobs to send email of any output you'll also need to install either exim or ssmtp (before running cron-config.)
See /usr/...
Get most recent file in a directory on Linux
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A minor issue: This version pipes all the output of ls to tail, then prints only the LAST line. IMHO it is better to sort in ascending order and use head instead, as chaos suggested. After printing the first line head quits, so sending the next line (actually...
How do I clear the terminal screen in Haskell?
...nal support, with Windows compatibility You can find it in Hackage and install using cabal install ansi-terminal. It specifically has functions for clearing the screen, displaying colors, moving the cursor, etc. Using it to clear the screen is easy: (this is with GHCI) import System.Console.ANSIclea...
Converting XML to JSON using Python?
... It's already been mentioned in newer answers. It still only covers a small subset of valid XML constructs, but probably the majority of what people use in practice.
– Dan Lenski
Dec 5 '18 at 11:48
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Linux: copy and create destination dir if it does not exist
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oops, right. But then, test may be a bash builtin (especially if written as [[ -d "$d" ]]) and mkdir can not ;-)
– Michael Krelin - hacker
Oct 7 '09 at 17:00
1
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Turn off constraints temporarily (MS SQL)
I'm looking for a way to temporarily turn off all DB's constraints (eg table relationships).
5 Answers
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How to construct a timedelta object from a simple string
...on, without having to resort to external libraries such as dateutil or manually parsing the input, is to use datetime's powerful strptime string parsing method.
from datetime import datetime, timedelta
# we specify the input and the format...
t = datetime.strptime("05:20:25","%H:%M:%S")
# ...and us...
How to convert from System.Enum to base integer?
... enum can have different underlying types (int, long, byte...).
More formally: System.Enum has no direct inheritance relationship with Int32 (though both are ValueTypes), so the explicit cast cannot be correct within the type system
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