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### python : Can't minimize the loss function

I am trying to minimize the loss function of radical estimates for estimating the parameters of the normal distribution

My code looks like this:

``````import numpy as np
from scipy import stats
from scipy.optimize import minimize
x= [1,2,3,4,5]
def oro (theta, x):
norma= 0
b= 1
u= theta 
o= theta 
x= np.array (x)
x0= 0
f0= -(((1 /(o * (2 * 3.14) ** (0.5))) * (2.718) ** -(((x0-u) ** 2) /(2 * (o ** 2 )))) ** b) ** -1
for i in range (x.size):
f= (1 /(o * (2 * 3.14) ** (0.5))) * (2.718) ** -(((x [i] -u) ** 2) /(2 * (o ** 2 ))) ** b
norma += f0 * f
return norma
theta_init= [0, 1]
res= minimize (oro, theta_init, args= x)
res
``````

But the output shows an error:

``````&lt;
ipython-input-81-ee81472a023a &gt;
: 8: RuntimeWarning: divide by zero encountered in double_scalars
f0= -(((1 /(o * (2 * 3.14) ** (0.5))) * (2.718) ** -(((x0-u) ** 2) /(2 * (o ** 2 )))) ** b) ** -1
&lt;
ipython-input-81-ee81472a023a &gt;
: 11: RuntimeWarning: invalid value encountered in double_scalars
norma += f0 * f
&lt;
ipython-input-81-ee81472a023a &gt;
: 8: RuntimeWarning: divide by zero encountered in double_scalars
f0= -(((1 /(o * (2 * 3.14) ** (0.5))) * (2.718) ** -(((x0-u) ** 2) /(2 * (o ** 2 )))) ** b) ** -1
&lt;
ipython-input-81-ee81472a023a &gt;
: 11: RuntimeWarning: invalid value encountered in double_scalars
norma += f0 * f
&lt;
ipython-input-81-ee81472a023a &gt;
: 8: RuntimeWarning: divide by zero encountered in double_scalars
f0= -(((1 /(o * (2 * 3.14) ** (0.5))) * (2.718) ** -(((x0-u) ** 2) /(2 * (o ** 2 )))) ** b) ** -1
&lt;
ipython-input-81-ee81472a023a &gt;
: 11: RuntimeWarning: invalid value encountered in double_scalars
norma += f0 * f
fun: nan
hess_inv: array ([[9.57096191e + 02, 2.41349815e + 01],
[2.41349815e + 01, 8.33412317e-01]])
jac: array ([nan, nan])
message: 'Desired error not necessarily achieved due to precision loss.'
nfev: 357
nit: 4
njev: 119
status: 2
success: False
x: array ([165623.69347712, 1751.95100725])
``````

Tell me, please, what am I doing wrong?

CrazyElf2021-11-25 10:09:02

What is the magic function minimize?

Andrew2021-11-25 10:10:14