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Creating a domain using a criterion A(x,y,z)>a

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How can I get a geometric domain C defined by a criterion A(x,y,z)>a where A is an interpolated 3d data from a text file, defined within a box B? I want to use C withn B to evaluate the integral of a 3d data Pr(x,y,z) within C.

Best, John


1 Reply Last Post 17 janv. 2023, 03:06 UTC−5
Gunnar Andersson COMSOL Employee

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Posted: 2 years ago 17 janv. 2023, 03:06 UTC−5

Do you really need an explicit representation of the region C? Computing the integral of Pr(x,y,z) * (A(x,y,z)>a) over B is mathematically equivalent to computing the integral of Pr(x,y,z) over C. The main drawback with using the integrand Pr(x,y,z) * (A(x,y,z)>a) is that the discontinuous second factor will lead to lower accuracy.

Do you really need an explicit representation of the region C? Computing the integral of Pr(x,y,z) * (A(x,y,z)>a) over B is mathematically equivalent to computing the integral of Pr(x,y,z) over C. The main drawback with using the integrand Pr(x,y,z) * (A(x,y,z)>a) is that the discontinuous second factor will lead to lower accuracy.

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