I'm exploring the simplex algorithm with a simple transportation problem of the form: minimize: 8a + 6b + 10c + 9d + 5e + 7f subject to the constraints: a + b + c = 11 d + e + f = 14 a + d = 10 b + e = 8 c + f = 7 I've implemented this in R (1.4.0 (2001-12-19), SunOS 5.7) as: require(boot) costs = c(8,6,10,9,5,7) constraints = c( 1,1,1,0,0,0, 0,0,0,1,1,1, 1,0,0,1,0,0, 0,1,0,0,1,0, 0,0,1,0,0,1 ) consmat = matrix(constraints, nrow=5, ncol=6, byrow=T) consrhs = c(11,14,10,8,7) simpres = simplex(a=costs, A3=consmat, b3=consrhs, maxi=F) where I get the error from the simplex function: Error in simplex1(out1$a[1:(n + m1 + m2)], out1$A[, 1:(n + m1 + m2)], : subscript out of bounds According to Gass (An Illustrated Guide to Linear Programming) the solution should be a=10, b=1, c=0, d=0, e=7, f=7 to minimize the objective function at 170. Have I misunderstood the use of the simplex function here? Thanks, Gerry Brush -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._