matlab load python scripts have different result when directly run in python

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I load a python user-defined scripts in Matlab but I got different results with Python.
In python, I have a function to calculate the numerical intergral of an intergral function.
In matlab load this python scripts by:
system('python Userdefined.py');
A = py.Userdefined.Intergral(0.2);
But here 'A' is different with python result when I directly run 'Intergral(0.2)' in python.
I have confirmed that, Matlab result is wrong but I don't know why!
I just load it in Matlab.
  5 Comments
KOU DU
KOU DU on 15 Jan 2021
I use system to load the python user-defined scripts.
Here I put an example of python script which is named 'Intergral.py':
#! /usr/bin/env python
import math
import sympy
from sympy import *
import numpy as np
from numpy import *
import scipy
from scipy import special
from scipy import *
from scipy.integrate import quad
from scipy import integrate
def da_theta_phi_np(p,theta,phi):
twop=2*p ; one_over_p=1./p ; one_over_twop=1./(2*p)
ct=np.cos(theta) ; st=np.sin(theta)
cp=np.cos(phi) ; sp=np.sin(phi)
r0=ct**twop+(st*cp)**twop+(st*sp)**twop
r=r0**(-one_over_twop)
tpm=twop-1.
drdtheta=(st*ct**tpm-ct*st**tpm*(cp**twop+sp**twop))\
*r0**(-one_over_twop-1)
drdphi=(st**twop*(cp*sp**tpm-sp*cp**tpm))\
*r0**(-one_over_twop-1)
st=np.sin(theta)
return r*np.sqrt((r*st)**2+(drdtheta*st)**2+drdphi**2)
def da_np(p,phi):
aux = quad(lambda theta: da_theta_phi_np(p,theta,phi), 0., acos(1./np.sqrt(2.+np.tan(phi)**2)))
res=aux[0]
return res
def surfacearea_np(p):
aux = quad(lambda phi: da_np(p,phi), 0., math.pi/4.)
res=aux[0]
return 48.*res
When I command in Matlab:
py.Intergral.surfacearea_np(0.2)
ans =
1.731011361308392
But I got 5.73153081591379 when I run in python. All results when I give input p<0.5 are different.
Ishan
Ishan on 28 Oct 2022
A call to the surfacearea_np with 0.2 as input gave an output of 1.7310113613083917 which is what MATLAB also gives. Essentially MATLAB just creates a call to the given function in the file you named 'Integral.py'. Do make sure you are calling the same function in your python script. Hope this helps!

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