"Mulholland, Tom" <[EMAIL PROTECTED]> writes: > > tdata > [,1] [,2] [,3] [,4] [,5] > [1,] 0 1 0 -1 -1 > [2,] 2 0 0 -5 -6 > [3,] 0 0 3 -5 -6 > [4,] 1 -1 -1 0 0 > > sumtd > [1] 0 0 0 -2 > > > > which I can calculate to give me 3x+30, x+12, 2x+20, 12x, x
[So presumably you want the complete solution of tdata %*% y == sumtd] I can't. 4th element should be just 12. > Would someone be kind enough to point me in the right direction as > to which tools I should be using and any sage words of advice for > the barely informed. Just move x*tdata[,5] (where x is y[5]) to the other side of the equation and solve for each column: > solve(tdata[,-5],sumtd) [1] 30 12 20 12 > zapsmall(solve(tdata[,-5],-tdata[,5])) [1] 3 1 2 0 (A general solution requires a bit more thought. E.g. you run into a singularity if you try the same idea with the 4th column instead of the 5th.) -- O__ ---- Peter Dalgaard Blegdamsvej 3 c/ /'_ --- Dept. of Biostatistics 2200 Cph. N (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
