Rasmus, your commits are these, right: https://gitlab.com/libeigen/eigen/-/commit/88d4c6d4c870f53d129ab5f8b43e01812d9b500e https://gitlab.com/libeigen/eigen/-/commit/be0574e2159ce3d6a1748ba6060bea5dedccdbc9
Which Array methods pick up these new packet methods? On Mon, May 10, 2021 at 7:53 PM Rasmus Munk Larsen <[email protected]> wrote: > I recently vectorized the implementation of pow in Eigen for float and > double arguments. It does not apply to pow(float, int), however, but > should give you a significant speedup if you cast your exponents to > double. I thought about implementing a more efficient algorithm if the > exponents are all integers, but didn't get round to it. Could you > please try if this helps you? The improvements are in the master > branch (as well as the 3.4 branch that we are preparing for release). > > On Mon, May 10, 2021 at 4:28 PM Marc Glisse <[email protected]> wrote: > > > > On Mon, 10 May 2021, Ian Bell wrote: > > > > > Of course, shortly after having sent this message I figured it out, > but it > > > doesn't actually result in an increase in my throughput sadly. For > > > posterity: > > > > > > #include <Eigen/Dense> > > > #include <iostream> > > > > > > using namespace Eigen; > > > > > > struct myUnaryFunctor { > > > const double m_base; > > > myUnaryFunctor(double base): m_base(base) {}; > > > typedef double result_type; > > > result_type operator()(const int &e) const > > > { > > > return pow(m_base, e); > > > } > > > }; > > > > > > int main() > > > { > > > auto e = Eigen::ArrayXi::LinSpaced(11, 0, 10).eval(); > > > double base = 2.9; > > > std::cout << e.unaryExpr(myUnaryFunctor(base)); > > > } > > > > Assuming pow is actually your own function and does the usual repeated > > squaring, unlike std::pow, this may do a lot of redundant computation (in > > particular base*base is computed many times). Do you know anything about > > the integers? In particular, are they always small? I assume the > LinSpaced > > example doesn't look like the true data. Does your pow function already > > cache some results? > > > > -- > > Marc Glisse > > > > > > >
