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Subject: Re: [ublas] Element-wise operations are really slow
From: xiss burg (xissburg_at_[hidden])
Date: 2010-04-23 12:27:32


Numbers swapped? Hm what do you mean?

Actually, my code looks like this now, much cleaner

for(int i=0; i<m_tetrahedrons.size(); ++i)
        btTetrahedron* t = m_tetrahedrons[i];

        for(unsigned int j=0; j<12; ++j)
            int jj = t->getGlobalIndex(j);

            for(unsigned int k=0; k<12; ++k)
                int kk = t->getGlobalIndex(k);

                m_RKR_1(jj, kk) += t->getCorotatedStiffness0(j, k);
                m_RK(jj, kk) += t->getCorotatedStiffness1(j, k);

If I change to +=1 I get the same performance. Also, if I comment only one
of these lines, m_RK(jj, kk)) += ... for example, I get exactly x2 speed up.
Oh well...

Thanks for you time and help.