[R] Solving Matrices

[Erich Neuwirth]

>>On April 15th, Elizabeth wrote:
>><snip>
>>
>>>(or x <- matrix(data=c(7, -5, 6, -7, 2, -3, 10, 9, -5,
>>>                       4, -2, 2, 8, -9, 7, 15), nrow=4, ncol=4)


qr(x)$rank
gives the rank
qr.R(qr(x))
gives the R part (an upper triangular matrix similar to the one
produced by Gauss elimination).
With the given matrix, we get rank 3, but the
last row of qr.R(qr(x)) is not 0 due to rounding errors.

-- 
Erich Neuwirth, Computer Supported Didactics Working Group
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