Does test whether the determinant is 0 suffice for you?
Roundoff issues & squareness issues can be dealt with,
but [EMAIL PROTECTED]:_ works too (not sure what issues arise).
det=:-/ . *
det i.3 3
0
det p:i.3 3
_78
liq=:0 ~: det NB. lin indep (cols or rows) query
liq i.3 3
0
liq p:i.3 3
1
NB. nonsquare, test columns for lin indep
det (+/ . * ~ |:) i.4 3
1.27898e_11
det (+/ . * ~ |:) p:i.4 3
29960
liq2=:1e_10 < |@det@:(+/ . * ~ |:)
liq2 i.4 3
0
liq2 p:i.4 3
1
Raul Miller wrote:
On 9/7/07, Raul Miller <[EMAIL PROTECTED]> wrote:
%:@%:^:_ p:i.3 3
1 1 1
1 1 1
1 1 1
[EMAIL PROTECTED]:_ p:i.3 3
2 3 5
7 11 13
17 19 23
--
Clifford A. Reiter
Mathematics Department, Lafayette College
Easton, PA 18042 USA, 610-330-5277
http://www.lafayette.edu/~reiterc
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