[R] selecting by variable

[Ko-Kang Kevin Wang]

On Wed, 27 Aug 2003, Eugene Salinas wrote:

> I'm a recent R convert so I haven't quite figured out
> the details yet...

Usually it is good to read the manuals when you use a unfamiliar 
software...

> How do I select one variable by another one? Ie if I
> want to draw the histogram of variable X only for
> those individuals that also have a value Y in a
> certain range?

e.g.
  x = rnorm(100)
  y = 1:100
  x[y = 20:50]
will give you the value of x when y is between 20 and 50.  To do a 
histogram, type:
  ?hist

-- 
Cheers,

Kevin

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--
Ko-Kang Kevin Wang
Master of Science (MSc) Student
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Department of Statistics
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