我与scipy.optimize.minimize
工作,而我优化3个参数有这样的功能
def foo(A, x, y, z):
test = my_function(A[0], A[1], A[2], x, y, z)
return test
在这个答案,我发现了一些见解:How to display progress of scipy.optimize function?所以我想出了这个功能:
def callbackF(Xi, x, y, z)
global Nfeval
print '{0:4d} {1: 3.6f} {2: 3.6f} {3: 3.6f} {4: 3.6f}'.format(Nfeval, Xi[0], Xi[1], Xi[2], foo(Xi, x, y, z))
Nfeval += 1
所以,我的代码看起来像这样
Optimal = minimize(fun=foo, x0=[fi, alfa, Ks], args=(x, y, z),
method='BFGS', callback=callbackF, tol=1e-2)
但我得到这个错误:
TypeError: callbackF() takes exactly 4 arguments (1 given)
我理解的错误,但我应该怎么避免呢?
如果你能仪器本身的功能,您可以随时DIY吧。唯一棘手位是迭代次数。对于它,你可以使用一个全球性的,或(IMO,更好)附加反函数本身:
>>> import numpy as np
>>> from scipy.optimize import minimize
>>>
>>> def f(x):
... res = np.sum(x**2)
... f.count += 1
... print('x = ', x, ' res = ', res, ' j = ', f.count)
... return res
...
>>> f.count = 0
>>> minimize(f, x0=5)
x = [ 5.] res = 25.0 j = 1
x = [ 5.00000001] res = 25.000000149 j = 2
x = [ 5.] res = 25.0 j = 3
x = [-5.] res = 25.0 j = 4
x = [-5.] res = 25.0 j = 5
x = [-4.99999999] res = 24.999999851 j = 6
x = [ 0.0005] res = 2.5e-07 j = 7
x = [ 0.0005] res = 2.5e-07 j = 8
x = [ 0.00050001] res = 2.50014901383e-07 j = 9
x = [ -7.45132485e-09] res = 5.55222420558e-17 j = 10
x = [ -7.45132485e-09] res = 5.55222420558e-17 j = 11
x = [ 7.44983634e-09] res = 5.55000615146e-17 j = 12
fun: 5.552224205575604e-17
hess_inv: array([[ 0.5]])
jac: array([ -1.48851092e-12])
message: 'Optimization terminated successfully.'
nfev: 12
nit: 2
njev: 4
status: 0
success: True
x: array([ -7.45132485e-09])