-- compare with
-- $ glpsol --cpxlp  /usr/share/doc/glpk-utils/examples/plan.lp  -o result.txt

import Numeric.LinearProgramming

prob = Minimize [0.03, 0.08, 0.17, 0.12, 0.15, 0.21, 0.38]

constr = Sparse
    [ [1#1,1#2,1#3,1#4,1#5,1#6,1#7]                          :==: 2000
    , [0.15#1, 0.04#2, 0.02#3, 0.04#4, 0.2#5,0.01#6, 0.03#7] :<=: 60
    , [0.03#1, 0.05#2, 0.08#3, 0.02#4, 0.06#5, 0.01#6]       :<=: 100
    , [0.02#1, 0.04#2, 0.01#3, 0.02#4, 0.02#5]               :<=:  40
    , [0.02#1, 0.03#2, 0.01#5]                               :<=:  30
    , [0.7#1,  0.75#2, 0.8#3,  0.75#4, 0.8#5,  0.97#6]       :>=:  1500
    , [0.02#1, 0.06#2, 0.08#3, 0.12#4, 0.02#5, 0.01#6, 0.97#7] :&: (250,300)
    ]

bounds = [ 1 :&: (0,200)
         , 2 :&: (0,2500)
         , 3 :&: (400,800)
         , 4 :&: (100,700)
         , 5 :&: (0,1500) ]

main = print $ simplex prob constr bounds