Can I calculate the absolute integral?

Elias Y. Daoud shared this question 3 weeks ago
Answered

Can I calculate the absolute integral? I mean can I get the positive or the negative part of an integral for a repetitive functions such sine wave - another sine wave?

In another words, the absolute surface.

Thanks

Comments (11)

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Please can you give an example of what you mean?

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I have a sine wave with variable amplitude (its amplitude equal to another bigger sine wave at variable t). I need its area above and below the X axis and the sum of integral is absolute value (not below x axis treated as negative, but positive). In my attachment, I need the absolute area of the green color. Thanks There are another problem,... discuss later (Integral limitation)

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help us if you attach your file. we need to know the function. meantime I only can do it with a own function that seems you want

Files: foro.ggb
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Hello, I already tried absolute abs function, and the Geogebra not able to integrate within.

Remark: After opening the file, do not turn f(x), f1(x) or g(x) on - to see the graph. The program need 2 minutes to show you one of them, and the system will be slow. Unless zoom in to not more than scale 10m, and turn them on.

I subdivide an integral to small segment [0, 450] it give a positieve&negative sum where I need the absolute sum. Also I need from 0 to 500000. So if I divide this interval it will be boring to solve it.

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if you want the total area, regardless of the sign of a function f, you can calculate the integral of abs(f).

chris

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me temo que estás superando con creces las capacidades de calculo del ordenador o las capacidades de memoria dedicada al java usado por GG

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If the roots are regularly spaced then you can do it like this:

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


If that doesn't help, please post your .ggb file

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Hello, I already tried this method, it cannot work. Because my function has n=666666 (500000/0.75)

So this impossible, Geogebra can solve up to 500 period, so I need to subdivide up to 1200 the process. I tried to use Sigma as below

Area=Sum(Sequence(IntegralBetween(....) and many similar ways... the capability cannot give a result,

And how to get the area regardless the sign? the integral cannot returned from abs(....)

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insisto en que este calculo debe exceder las capacidades de casi cualquier ordenador personal

puede intentar maxima,mathlab,wolfram etc, pero creo que será inútil, quizás la NASA

la unica forma que veo es hacer un estudio eexhaustivo de cada onda y la parte que ocupa dentro de la onda superior y buscar algun proceso por induccion si lo hay

GG viene a congelarse con listas de 10000 numeros así que 666666 son como dos demonios

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it is here https://help.geogebra.org/t...

aun así supera las capacidades de memoria según yo creo

hay alrededor de 100000 trozos. lo mejor es calcular el area para un trozo generico y luego hacer una serie

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Still not solved. I made already a series, but need 1100 series of big number of repetitive interval

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