Try using outer: outer(1:3, a, "==")+0
On 8/31/06, z s <flyhyena at yahoo.com.cn> wrote:
Hi,
I am trying to convert a variable a = sample(1:3,100,rep = T) represents choices into a 3X100 dummy varible b with corresponding element set to 1 otherwise 0.
eg.
a: 1 3 2 1 2 3 1 1....
b: 1 0 0 1 0 0 1 1..
0 0 1 0 1 0 0 0...
0 1 0 0 0 1 0 0...
Is there something like b[a] =1 existing? I could not figure this out myself.
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Mp3??????-??????????????
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