我尝试使用拉格朗日乘数来优化函数,我试图遍历函数来获取数字列表,但是我得到了错误
ValueError: setting an array element with a sequence.
这是我的代码,我哪里出错了?如果n不是数组,我可以正确地得到结果
import numpy as np
from scipy.optimize import fsolve
n = np.arange(10000,100000,10000)
def func(X):
x = X[0]
y = X[1]
L = X[2]
return (x + y + L * (x**2 + y**2 - n))
def dfunc(X):
dLambda = np.zeros(len(X))
h = 1e-3
for i in range(len(X)):
dX = np.zeros(len(X))
dX[i] = h
dLambda[i] = (func(X+dX)-func(X-dX))/(2*h);
return dLambda
X1 = fsolve(dfunc, [1, 1, 0])
print (X1)
非常感谢,非常感谢
答案 0 :(得分:2)
首先,检查func = fsolve()
第二,打印(func([1,1,0]))` - 结果不是数字([2 2 2 2 2 2 2 2 2]),beause" n"是清单。如果你想迭代n尝试:
import numpy as np
from scipy.optimize import fsolve
n = np.arange(10000,100000,10000)
def func(X,n):
x = X[0]
y = X[1]
L = X[2]
return (x + y + L * (x**2 + y**2 - n))
def dfunc(X,n):
dLambda = np.zeros(len(X))
h = 1e-3
r = 0
for i in range(len(X)):
dX = np.zeros(len(X))
dX[i] = h
dLambda[i] = (func(X+dX,n)-func(X-dX,n))/(2*h)
return dLambda
for iter_n in n:
print("for n = {0} dfunc = {1}".format(iter_n,dfunc([0.8,0.4,0.3],iter_n)))