Bryan L. Brown wrote:
Sorry if these questions have been asked recently--I'm new to this
list.

Hi Bryan,

A useful resource is Robin Hankin's contributed document "R and Octave":

http://cran.r-project.org/doc/contrib/R-and-octave-2.txt


The first is Matlab's 'find' command. This is one of the most useful
commands in Matab.  Basically, if X is the vector

X=[3, 2, 1, 1, 2, 3]

the command

'find(X==1)'

would return the vector [3, 4]

> x <- c(3, 2, 1, 1, 2, 3) > which(x == 1) [1] 3 4



The second Matlab command that I'd like to find an R equivalent for is 'end'. 'end' is just a simple little command that indicates the end of a row/column. It is incredibly handy when used to subset matrices like

Y = X(2:end)

and produces Y=[2, 1, 1, 2, 3] if the X is the same as in the
previous example.

> Y <- x[-1] > Y [1] 2 1 1 2 3

Not quite the same I'll grant you, but results in the same thing. If you wanted Y = X(4:end) you could use:

> Y <- x[-c(1:3)]
> Y
[1] 1 2 3

HTH

Gav
--
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Gavin Simpson                     [T] +44 (0)20 7679 5522
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