Hi,
Sorry to bother with something that should be simple, but I can't find it.
Suppose I have a list, each element of which is a 2xN dataframe, where N
could be different for each element.
Is there some simple structure to let me examine all the elements of
each element's first column? For example:
>foo
$first
[,1] [,2]
[1,] 1 4
[2,] 2 5
[3,] 3 6
$second
[,1] [,2]
[1,] 1 6
[2,] 2 8
[3,] 3 6
[4,] 4 8
To find the maximum element in all first columns (say, to set the range
of a plot where all first columns are x-data), I'd like the legal
equivalent of
>max(foo[[*]][,1])
(where here "*" is a wildcard intended to span all elements of foo)
Or do I have to use one of the apply() functions?
thanks
Carl
try: max(sapply(foo, max)) On Tue, Oct 14, 2008 at 5:49 PM, Carl Witthoft <carl at witthoft.com> wrote:> Hi, > Sorry to bother with something that should be simple, but I can't find it. > > Suppose I have a list, each element of which is a 2xN dataframe, where N > could be different for each element. > Is there some simple structure to let me examine all the elements of each > element's first column? For example: > >>foo > $first > [,1] [,2] > [1,] 1 4 > [2,] 2 5 > [3,] 3 6 > > $second > [,1] [,2] > [1,] 1 6 > [2,] 2 8 > [3,] 3 6 > [4,] 4 8 > > To find the maximum element in all first columns (say, to set the range of a > plot where all first columns are x-data), I'd like the legal equivalent of > >>max(foo[[*]][,1]) > (where here "*" is a wildcard intended to span all elements of foo) > > Or do I have to use one of the apply() functions? > > thanks > Carl > > ______________________________________________ > R-help at r-project.org mailing list > 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. >-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve?
actually meant to say: max(sapply(foo, function(x) max(x[,1]))) On Tue, Oct 14, 2008 at 5:49 PM, Carl Witthoft <carl at witthoft.com> wrote:> Hi, > Sorry to bother with something that should be simple, but I can't find it. > > Suppose I have a list, each element of which is a 2xN dataframe, where N > could be different for each element. > Is there some simple structure to let me examine all the elements of each > element's first column? For example: > >>foo > $first > [,1] [,2] > [1,] 1 4 > [2,] 2 5 > [3,] 3 6 > > $second > [,1] [,2] > [1,] 1 6 > [2,] 2 8 > [3,] 3 6 > [4,] 4 8 > > To find the maximum element in all first columns (say, to set the range of a > plot where all first columns are x-data), I'd like the legal equivalent of > >>max(foo[[*]][,1]) > (where here "*" is a wildcard intended to span all elements of foo) > > Or do I have to use one of the apply() functions? > > thanks > Carl > > ______________________________________________ > R-help at r-project.org mailing list > 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. >-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve?