[R] Understanding which

[Jeff Newmiller]

Look at

which(x>100)

This is a zero-length vector. The negative of nothing is nothing, not a list of all possible index values.

Do you want

x[ !( x > 100 ) ]

?

On April 18, 2018 6:13:30 AM CDT, Ashim Kapoor <ashimkapoor using gmail.com> wrote:
>Dear All,
>
>Here is a reprex:
>
>> x<- 1:100
>> x[-which(x>100)]
>integer(0)
>
>In words, I am finding out which indices correspond to values in x
>which
>are  greater than  100 ( there are no such items ) . Then I remove
>those
>indices. I should get back the x that I started with since there are no
>items in x which are bigger than 100 . Instead, it is returning an
>empty
>vector.
>
>Why is this ? What am I misunderstanding?
>
>Best Regards,
>Ashim
>
>	[[alternative HTML version deleted]]
>
>______________________________________________
>R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide
>http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.

-- 
Sent from my phone. Please excuse my brevity.