Maximum Point from CubicSpline for Excel or Alibre Script

[GIOV]

Hi Guys
I have a big questions:
1.-How run a scipy CubicSpline in Alibre Script or Excel?

import numpy as np
from scipy.interpolate import CubicSpline
import matplotlib.pyplot as plt
x = np.arange(10)
y = np.sin(x)
cs = CubicSpline(x, y)
xs = np.arange(-0.5, 9.6, 0.1)
fig, ax = plt.subplots(figsize=(6.5, 4))
ax.plot(x, y, 'o', label='data')
ax.plot(xs, np.sin(xs), label='true')
ax.plot(xs, cs(xs), label="S")
ax.plot(xs, cs(xs, 1), label="S'")
ax.plot(xs, cs(xs, 2), label="S''")
ax.plot(xs, cs(xs, 3), label="S'''")
ax.set_xlim(-0.5, 9.5)
ax.legend(loc='lower left', ncol=2)
plt.show()

2,0 How find the Maximum Point of a CubicSpline?

from scipy.interpolate import InterpolatedUnivariateSpline
f = InterpolatedUnivariateSpline(x_axis, y_axis, k=4)
cr_pts = f.derivative().roots()
cr_pts = np.append(cr_pts, (x_axis[0], x_axis[-1])) # also check the endpoints of the interval
cr_vals = f(cr_pts)
min_index = np.argmin(cr_vals)
max_index = np.argmax(cr_vals)
print("Maximum value {} at {}\nMinimum value {} at {}".format(cr_vals[max_index], cr_pts[max_index], cr_vals[min_index], cr_pts[min_index]))

Uff, it is so difficult for me this issue.
Ref.:

CubicSpline — SciPy v1.14.1 Manual

docs.scipy.org

 

[stepalibre]

These projects are Python 3, numpy and scipy can be pip or conda installed in them.

GitHub - stephensmitchell/gmsh-dotnet: Gmsh + Python + .Net

Gmsh + Python + .Net. Contribute to stephensmitchell/gmsh-dotnet development by creating an account on GitHub.

github.com

GitHub - stephensmitchell/freecad-dotnet: FreeCAD + Python + .Net

FreeCAD + Python + .Net. Contribute to stephensmitchell/freecad-dotnet development by creating an account on GitHub.

github.com

GitHub - stephensmitchell/blender-dotnet: Blender + Python + .Net

Blender + Python + .Net. Contribute to stephensmitchell/blender-dotnet development by creating an account on GitHub.

github.com

They use PythonNet which can talk to AD (Alibre Script and AlibreX) from .NET several ways.

You can export coordinates and geometry info to csv or text from Python to use in Excel or Alibre Script.

Excel has Python support now so if you can get it up and running it might be the easy way to answer both questions:

min_index = np.argmin(cr_vals)
max_index = np.argmax(cr_vals)

What is the issue? You can review numpy documentation for max and min.

 

[GIOV]

Hi Stepalibre,
Thanks for your answer.
I like to try in Alibre:
So I will import a CubicSpline curve from my old excel and try to apply the above "from scipy.interpolate import CubicSpline" code that I find.
Is it correct?
If correct, library resources are enormous.