[R] indexing a vector

[Jeff Miller]

----- Original Message -----
From: Thomas Lumley <tlumley at u.washington.edu>
Sent: Monday, May 07, 2001 1:38 PM

> On Mon, 7 May 2001, David White wrote:
>
> >
> > Dear R-List,
> >
> > How can one look up the row/column number for a given value in a matrix
or
> > data.frame?  For example in a matrix that contains only unique values
for
> > in [,1] how can I find value x in [,1] and report its row number?
> >
>
> match(x,matrix[,1])
>
> -thomas

    As a follow up to this question,  what's the easiest way to
    find the column and row indicies for a specified value in a matrix,
    when you don't know which column it's in (as assumed above)?

    So if   mymatrix <- matrix(c(3, 2, 4, 1), nrow = 2),  what's the easiet
way
    to see that the value 4 is in position (1, 2) ?

    Thanks much,

        Jeff Miller





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