Interpolation - Polynomial - 3D Graph

[Anousheh]

1- Hello everybody,

1- How do I perform a cubic interpolation of a function with 3 variables? I have Zf(ρ,α,X0)

2- 2- After interpolation, How do I generate the actual cubic polynomial with my 3 variables?

3- 3- How do I make a 3D graph showing my results?

I have attached my calculation in a MathCad file (ver.14). Please go to the end of the worksheet to see my work on the problems mentioned above.

I had to do the interpolation manually. i.e. creating vectors for ρ, α and X0. You can see that I could generate polynomial coefficients (20 of them!) but, don’t know how to create the actual polynomial.

The polynomial written in the worksheet (highlighted) is done by generating the coefficients in EXCEL.

Important task would be to do the interpolation by using my original function and variables.

Thank you so much for your time and help.

Anousheh

[ValeryOchkov]

If we have f(x, y, z) it will be better plot not a surface but three X-Y plot.

See one example here

May by it is better use spline interpolation:

And second.

Send please not full sheet but an extract from sheet with your question!

[Anousheh]

Thank you so much.

I am trying to extract from the large worksheet only the needed part.

Please be patient.

Thanks

[Anousheh]

Hello,

I have attached the extracted MathCad file.

Thank you so much.

Just do the modification at the bottom of the worksheet.

I appreciate your help.

[MikeArmstrong]

Just a little advice. I would recommend like Valery said only posting the actual problem or data within the worksheet.

I can only speak for myself, but I am imediatly put off when I see a large worksheet (>300kb) uploaded. It is much easdier and less time consuming when the actual problem is displayed so the collab doesn't have to scroll through the sheet.

Mike

[Anousheh]

Thank you.

I am trying to do that.

[Anousheh]

Hello,

I have attached the file (extract).

Please help me to do this.

Thank you so much.