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ScalarField division

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Old   August 26, 2007, 17:57
Default I do the following operation b
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Maka Mohu
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I do the following operation but it gives wrong result (1.22005e-312):

const scalarField& ry = patch().deltaCoeffs();
// magnitude of patch-normal distance from face to cell centers:
const scalarField& yn= 1.0/ry;

but if I make a loop and use:

const scalarField& yn= 1.0/ry[facei];

it gives correct result. How can I do mathematical operations that contain scalarFields and scalars without looping? Thanks.

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Maka
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Old   August 26, 2007, 18:16
Default Classic mistake: reference to
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Hrvoje Jasak
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Classic mistake: reference to a temporary: if you do:

scalarField yn= 1.0/ry;

all will be well. Operation 1/ry will return a COPY, i.e. a new field. You took a reference to it, which is a memory error - that's the little & bit after the scalarField.

I bet you already know this - if not, time for a careful look at a good C++ book.

Got it?

Hrv
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Old   August 27, 2007, 05:10
Default Thanks Hrv for the explanation
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Maka Mohu
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Thanks Hrv for the explanation.
Best regards,
Maka.
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