Is there a way to reference a matrix so that it knows its position in another matrix?

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zephyr21 2016-6-19

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评论： Walter Roberson 2016-6-20

Test.m

Is there a better way to reference this table? the i and j columns are referring to a specific point inside an 11x14 matrix. Looking at the example code I have posted, Q is an 11x14 matrix. My code is stating that Q(4,10)=... by making this convoluted reference Q((Well(nn,6),Well(nn,7)). Is there a better way to do this?

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Answer 1

Walter Roberson 2016-6-20

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No, that is appropriate code.

As a matter of clarity I would use a temporary vector, something like

for nn=1:NumWell
    thiswell = Well(nn,:);
    if thiswell(2) == 5
       i = thiswell(6); j = thiswell(7);
       Q(i, j) = Q(i, j) - thiswell(4);
       Rate1(i, j) = - thiswell(4);
    end
end

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zephyr21 2016-6-20

That helps tidy up the code a bit. But the reason I was asking is because in another string of code following this, I need to say that if the pressure of a specific spot in another 11x14 matrix falls below the number in the table, then make the rate zero

Walter Roberson 2016-6-20

The same principles apply: for clarity, assign to temporary variables. This is not necessarily going to lead to faster code, but unless the code is going to be executed a lot, the larger cost is in programming and debugging, so write first to be able to understand the code.

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