Finding the functions between these points

anas4503 shared this question 9 months ago
Answered

I have the following vase and I wish to find the functions between each of the points so that I can integrate it to find hte volume. So how do I find the functions? I saw one can do fitpoly command but that doesnt look like itll work with these points:


86b8dfe567940743f8535b7d4818b849

Comments (18)

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Use more points and experiment with the degree.

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Also try Spline() or you can draw a freehand function with the Freehand Shape tool

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Try this applet that uses trigonometric interpolation.

First draw your shape with Penstroke and then click on Plot Epicycles. Finally click on Equation button.

0e57e93ad6d0acde1a6b0babed418ac8

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Very cool! Is that uploaded to geogebra.org?

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por fin la busqueda sirvio para algo

https://www.geogebra.org/m/dubc9swj

pero me gusta mas el del post

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There is one but it I have not published it because the results are quite different online compare to the offline version.

https://www.geogebra.org/m/tgbjxehq

I also made it with points:

https://www.geogebra.org/m/sgmheqay

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Thanks, that's amazing!

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Hello Juan,

Thank you for the reply, I tried using this trigonometric interpolation program but I dont know how it works. Is it possible you can show me how to and help me with this? I am in my last year of high school and this assignment weighs 25% of my final grade, so I would really appreciate if you could show me how to work it out.

Kindest Regards,

Anas

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To work out the trigonometric interpolation you can consult this material:

http://www-users.math.umn.e...

You are going to need some time to study it but I think I may help. Cheers!

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Thanks for the theory part, I think I now know what an epicycle is. But when using your program, it makes the epicycles but then it doesnt display the trigonometric equation.. How would I do that?

I have attached my work if you want to see if it is possible.

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For example, I've attached an image that shows me work where I roughly estimated the points of my vase onto that program you showed me. But then when I click on plot epicycles it gives this: (attached), and I cant get the equation out of it.

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Epicycles won't give you an equation. Try FitPoly() or Spline()

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If you want the equation you need the file shared at the beginning:

https://help.geogebra.org/t...

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es evidente que si nos compartiera el archivo con la imagen de la botella ya le habríamos dado las funciones necesarias para saber el volumen de la botella, pero como las personas parecen cada vez más reacias a compartir sus *.ggb estamos dando indicaciones una y otra vez, lo que a la larga supone una perdida de tiempo

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Juan Carlos

como no me funciona no entiendo el funcionamiento

lo he abierto y el script del boton1 me abruma, pero cuando hago clic en el boton plot epicycles me crea otro stroke que tiene el grafico nulo y no hace nada más

puede que el script no funcione en ver5 escritorio

¿es necesario abrirlo online tal vez?

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ya lo he visto y funciona tela de bien

me voy a pasar las navidades mirandolo junto con el enlace de michael a las series de fourier, que veo te has leido a fondo

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Que bueno que lo has podido abrir. Si tienes mas problemas hazmelo saber.

Tambien escribi un post en mi blog acerca de esto https://bestiariotopologico...


Saludos.

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