gurobi simple python example

导师让学gurobi，安装了anaconda，用python在jupyterlab按例子练练手,pycharm里不会连gurobipy的接口.
$$\begin{gathered} \max =x+y+2z \\ s.b\{\begin{array}{ll}x+2y+3z& \le 4\\ x+y& ⩾1\\ x,y,z& binary\end{array} \end{gathered}$$

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from gurobipy import*

m=Model("mip1")

x=m.addVar(vtype=GRB.BINARY,name="x")
y=m.addVar(vtype=GRB.BINARY,name="y")
z=m.addVar(vtype=GRB.BINARY,name="z")

m.setObjective(x+y+2*z,GRB.MAXIMIZE)
m.addConstr(x+2*y+3*z<=4,"c0")
m.addConstr(x+y>=1,"c1")

m.optimize()

for v in m.getVars():
    print(v.varName, v.x)
print('Obj:', m.objVal)
#except GurobiError:
#    print("Error")

Optimize a model with 2 rows, 3 columns and 5 nonzeros
Variable types: 0 continuous, 3 integer (3 binary)
Coefficient statistics:
  Matrix range     [1e+00, 3e+00]
  Objective range  [1e+00, 2e+00]
  Bounds range     [1e+00, 1e+00]
  RHS range        [1e+00, 4e+00]
Found heuristic solution: objective 2.0000000
Presolve removed 2 rows and 3 columns
Presolve time: 0.00s
Presolve: All rows and columns removed

Explored 0 nodes (0 simplex iterations) in 0.01 seconds
Thread count was 1 (of 8 available processors)

Solution count 2: 3 2 

Optimal solution found (tolerance 1.00e-04)
Best objective 3.000000000000e+00, best bound 3.000000000000e+00, gap 0.0000%
x 1.0
y 0.0
z 1.0
Obj: 3.0