[Python] fsolve (scipy) results in ValueError

I am solving so called Blasius problem. I use the following code (copied from youtube lecutre https://www.youtube.com/watch?v=0L4h-hqZY2Y , timecode: 8:35):

import numpy as np
import matplotlib.pyplot as plt
from scipy.integrate import odeint
from scipy.optimize import fsolve
from scipy.optimize import root
from scipy.optimize import root_scalar

eta = np.linspace(0, 10, 101)

def blas(f, t):
return (f[1], f[2], -(1/2)*f[2]*f[0])

def blas0(x, ts):
f0 = (0., 0., x)
f = odeint(blas, f0, ts)
return 1.-f[-1, 1]

print(blas0(0.0, eta))
print(blas0(0.1, eta))
print(blas0(0.2, eta))
print(blas0(0.332, eta))
print(eta)

xpp0 = fsolve(blas0, x0=0.1, args=(eta), xtol=1e-6)


All the listed print-functions work well and print correct results. However, the function fsolve results in the following error:

xpp0 = fsolve(blas0, x0=0.1, args=(eta), xtol=1e-6)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...
ValueError: setting an array element with a sequence. The requested
array has an inhomogeneous shape after 1 dimensions. The detected
shape was (3,) + inhomogeneous part.

• I tried to downgrade numpy and scipy packages.
• I tried to add dtype=object in definition of eta.
• I tried to use the function root instead of fsolve.
• I tried to use other solutions found here (or in google).

Neither of these methods work.

The packages list:

Package Version
--------------- -----------
contourpy 1.3.0
CoolProp 6.6.0
cycler 0.12.1
fonttools 4.53.1
kiwisolver 1.4.7
matplotlib 3.9.2
numpy 2.1.1
packaging 24.1
pandas 2.2.2
pillow 10.4.0
pip 24.2
pyparsing 3.1.4
PyQt6 6.7.1
PyQt6-Qt6 6.7.2
PyQt6_sip 13.8.0
python-dateutil 2.9.0.post0
pytz 2024.2
scipy 1.14.1
six 1.16.0
tzdata 2024.1



Does anybody knows what the problem can be?

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