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"""
The Sponge Roll Problem with Columnwise Column Generation for the PuLP Modeller
Authors: Antony Phillips, Dr Stuart Mitchell 2008
"""
# Import Column Generation functions
from CGcolumnwise import *
# The Master Problem is created
prob, obj, constraints = createMaster()
# A list of starting patterns is created
newPatterns = [[1,0,0],[0,1,0],[0,0,1]]
# New patterns will be added until newPatterns is an empty list
while newPatterns:
# The new patterns are added to the problem
addPatterns(obj,constraints,newPatterns)
# The master problem is solved, and the dual variables are returned
duals = masterSolve(prob)
# The sub problem is solved and a new pattern will be returned if there is one
# which can reduce the master objective function
newPatterns = subSolve(duals)
# The master problem is solved with Integer Constraints not relaxed
solution, varsdict = masterSolve(prob,relax = False)
# Display Solution
for i,j in list(varsdict.items()):
print(i, "=", j)
print("objective = ", solution)
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