Hi All,
(I have a degree in math, but I am too embarassed to ask my colleagues, so here goes:)
I would like to get a vector normal (orthogonal) to a plane formed by two other vectors. In matlab I do this:
v1 = [.4, .6, .8]; v2 = [.9, .7, .2]; nn = cross(v1,v2) (gives ~[-.48, .65, -.24]
Huh?
I don't have access to Matlab. Can you tell me how cross() is defined in Matlab (it's not obvious to me - at least not at 10:40 pm - how can anything get negative)?
if I do R> cross(v1, v2), I get .94. Huh?
Ha! ;-)
crossprod(v1, v2): 0.4*0.9 + 0.6*0.7 + 0.8*0.2 = 0.94
Uwe Ligges
Thanks for all your help, again.
W
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