示例一:
import numpy as np
import matplotlib.pyplot as mpl
from scipy import optimize
c=np.array([3,1])
a=np.array([[2,1],[1,1]])
b=np.array([1,1])
res=optimize.linprog(-c,A_ub=a,b_ub=b,bounds=((0,None),(0,None)))
'''
max z = 3x+y
2x+y<=1 , A_ub[0]=[2,1], b_ub[0]=1
x+y<=1 , A_ub[1]=[1,1],b_ub[1]=1
x>=0,y>=0 , (0,None)->(0,+无穷)
//若2x+y=3, 则A_eq=[2,1], b_eq=[3]
'''
print (res.x)
print (res.fun) #res.fun可能受函数传入参数-c的影响,需要取反才是所求最大值
示例二:
min−7x1+7x2−2x3−x4−6x5
m
i
n
−
7
x
1
+
7
x
2
−
2
x
3
−
x
4
−
6
x
5
3x1−x2+x3−2x4=−3
3
x
1
−
x
2
+
x
3
−
2
x
4
=
−
3
2x1+x2+x4+x5=4
2
x
1
+
x
2
+
x
4
+
x
5
=
4
−x1+3x2−3x4+x6=12
−
x
1
+
3
x
2
−
3
x
4
+
x
6
=
12
x1>=0...x6>=0
x
1
>=
0
.
.
.
x
6
>=
0
import numpy as np
import matplotlib.pyplot as mpl
from scipy import optimize
c=np.array([-7,7,-2,-1,-6,0])
a=np.array([[3,-1,1,-2,0,0],[2,1,0,1,1,0],[-1,3,0,-3,0,1]])
b=np.array([-3,4,12])
res=optimize.linprog(c,A_eq=a,b_eq=b,bounds=((0,None),(0,None),(0,None),(0,None),(0,None),(0,None)))
print (res.x)
print (res.fun)
参考网站:
https://docs.scipy.org/doc/scipy/reference/generated/scipy.optimize.linprog.html#scipy.optimize.linprog
scipy.optimize.linprog(c, A_ub=None, b_ub=None, A_eq=None, b_eq=None, bounds=None, method=’simplex’, callback=None, options=None)