Ok. It's done. Just to be sure I understood what I read on a github forum; there is no way for me to attach a label to the PR. So the labels are always added by someone else ?
--John On Monday, January 5, 2015 9:25:18 PM UTC+1, Viral Shah wrote: > > Thanks. Do create a PR. > > -viral > > > > > On 06-Jan-2015, at 1:53 am, lapeyre....@gmail.com <javascript:> wrote: > > > > I meant randbool() in v0.3, where it was a more direct call, not > randbool() in v0.4. > > Anyway, I just found the problem and patched it. Adding one '@inline' > now makes rand(Bool) in v0.4 > > about as fast as randbool() in v0.3. > > > > Should I open an issue (bug report), or just make a PR ? > > > > On Monday, January 5, 2015 8:59:02 PM UTC+1, Viral Shah wrote: > > I doubt that rand(Bool) is any slower, since randbool() calls > rand(Bool). It is worth filing this as a performance regression. > > > > -viral > > > > On Monday, January 5, 2015 9:41:45 PM UTC+5:30, lapeyre....@gmail.com > wrote: > > It may be in part the implementation of the RNG. I think it is also in > part whether the abstraction is optimized away. > > Notice that Julia v0.3 is faster than v0.4. This is probably randbool() > vs. rand(Bool). > > > > On Monday, January 5, 2015 4:50:56 PM UTC+1, Isaiah wrote: > > Very neat. Just in case this gets posted to the interwebz, it is worth > pointing out that the performance advantage for Julia can probably be > explained by differences in the underlying RNG. We use dsFMT, which is > known to be one of (if not the?) fastest MT libraries around. I could not > find any published comparisons in a quick google, but based on this test > harness [1], dsFMT may be significantly faster than std::mt19937: > > > > ``` > > ihnorton@julia:~/tmp/cpp-random-test$ ./random-real > > C++11 : 2.34846 > > Boost : 0.371674 > > dSFMT : 0.281255 > > GSL : 0.649981 > > ``` > > > > [1] https://github.com/yomichi/cpp-random-test > > > > > > On Mon, Jan 5, 2015 at 10:12 AM, <lapeyre....@gmail.com> wrote: > > Oh, and, (I forgot to mention!) the Julia code runs much faster. > > > > > > On Monday, January 5, 2015 3:56:07 PM UTC+1, lapeyre....@gmail.com > wrote: > > Hi, here is a comparison of Julia and C++ for simulating a random walk. > > > > It is the first Julia program I wrote. I just pushed it to github. > > > > --John > > > > > >
