[R] Converting a list to a matrix - I still don't think I hav e it right

[Liaw, Andy]

Try:

mat <- do.call("rbind", l2)

Not sure if the names get put into the rownames automatically, but if not,
just do:

rownames(mat) <- names(l2)

Andy

> From: michael watson (IAH-C)
> 
> Hi
> 
> We have touched on this before, but I don't think I quite got 
> it right.
> 
> So I have a list, each element of which is a a vector of 2 numbers:
> 
> > l2
> $cat000_a01
> [1] 0.3429944 4.5138244
> 
> $cat000_a02
> [1] 0.1929336 4.3064944
> 
> $cat000_a03
> [1] -0.2607796  4.1551591
> 
> What I actually want to convert this into is a matrix with the names
> (cat000_a01 etc) as row names, the first element of each of 
> the vectors
> forming the first column of the new matrix, and the second element of
> each of the vectors forming the second column:
> 
> cat000_a01	0.3429944	4.5138244
> cat000_a02	0.1929336	4.3064944
> cat000_a03	-0.2607796  4.1551591
> 
> What was suggested on the list last time was
> matrix(unlist(mylist),nrow=length(mylist)).  But if I do this I get:
> 
> > matrix(unlist(l2),nrow=length(l2))
>           [,1]       [,2]
> [1,] 0.3429944  4.3064944
> [2,] 4.5138244 -0.2607796
> [3,] 0.1929336  4.1551591
> 
> Which is not what I want.  Here, the second element of the 
> first vector
> in my list has gone into the first column of the new matrix, 
> and that's
> not what I want at all.
> 
> Any more help would be appreciated.
> 
> Thanks
> Mick
> 
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