Division between elements of matrices

Division between elements of matrices - Messaggi

#1 Pubblicato: 26/05/2013 07:08:29
experimentator

experimentator

1 apprezzamenti in 21 post.

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First of all, I think Andrey the work you do is astonishing and thanks to all the community, too.

I have a problem, waht is wrong?


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#2 Pubblicato: 26/05/2013 08:25:00
Mike Kaganski

Mike Kaganski

184 apprezzamenti in 434 post.

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1. You should not use i's and j's as indices, because they also designate imaginary part of complex numbers. In some versions some of them, or both, cause errors when used otherwise.
2. You could use I and j as indices of k, not of C[k] or A[k].

It would be better if you attach the file.


Edit: Oh, it looks like you cannot assign anything to nested matrices...
Seems like you only can assign the whole new matrix to C[k].
С уважением, Михаил Каганский
#3 Pubblicato: 26/05/2013 08:30:38
Radovan Omorjan

Radovan Omorjan

325 apprezzamenti e 1 disapprezzamenti in 2.052 post.

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Hello,

Try this


[MATH=eng]for(k,range(1,rows(A)),line(for(i,range(1,rows(),for(j,range(1,cols(),el(c,i,j):el(B,i,j)/el(el(A,k),i,j))),el(C,k):c,2,1))[/MATH]


[MATH=eng]C=mat(mat(4,2.5,2,1.75,1.6,1.5,3,2),mat(0.571,0.625,0.667,7,4,3,3,2),2,1)[/MATH]

It seems that direct assignment of a matrix element in a nested matrix is not allowed. Try to avoid such constructions - it will give trouble.

Regards,
When Sisyphus climbed to the top of a hill, they said: "Wrong boulder!"
#4 Pubblicato: 26/05/2013 08:30:52
Martin Kraska

Martin Kraska

1.361 apprezzamenti in 2.275 post.

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The problem is in using nested indices on the left hand side. That does not work just as linear indexing of pre-allocated matrices does not work (would save a loop in the example).


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Technische Mechanik mit SMath Studio: https://link.springer.com/book/10.1007/978-3-658-50592-9
#5 Pubblicato: 26/05/2013 13:58:08
experimentator

experimentator

1 apprezzamenti in 21 post.

Gruppo: User

I thank you all!
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