Hi again, Just to let you know about the issue I just opened in Github:
https://github.com/JuliaLang/julia/issues/7342 Thank you for everything! Best, Charles On Fri, Jun 20, 2014 at 10:07 PM, Charles Novaes de Santana < charles.sant...@gmail.com> wrote: > Thank you, Dahua! > > I will open an issue in Github as suggested by you. In meanwhile I will > see if by using sum I can get a better performance. > > Best, > > Charles > > > On Fri, Jun 20, 2014 at 5:54 PM, Dahua Lin <linda...@gmail.com> wrote: > >> The cumsum / cummax / cummin / cumprod, etc have suboptimal performance >> currently, which are about 20x slower than the sum/prod etc (which we spent >> a lot of efforts to optimize and tune). >> >> Please open an issue in Github, and we will try to address this problem >> later. >> >> Dahua >> >> >> On Friday, June 20, 2014 10:15:55 AM UTC-5, Charles Santana wrote: >>> >>> Dear Julia users, >>> >>> First of all, Congratulations for this amazing community and for this >>> impressive language! I used to program in C++ and in R, I started to >>> program with Julia 3 months ago and it has changed my life for better!! >>> Thank you!! >>> >>> By checking the profile of a program we are developing we noted that the >>> "bottleneck" seems to be in a cumulative sum along a dimension in a matrix, >>> for what we use the function cumsum. >>> >>> We are doing something like this: >>> >>> DI = rand(5,5); >>> Dc = cumsum(DI,2); >>> >>> Just to try to clarify what we are doing: Imagine that Matrix DI(i,j) >>> represents the probability of an individual to move from a site i to a site >>> j. We use Dc to determine to which site an individual in site i will move, >>> by generating a random number between 0 and maximum(Dc[i,:]). That means, >>> we are trying to perform a Multinomial Distribution. >>> >>> Do you know an alternative to cumsum or do you indicate a good way to >>> use this function. >>> >>> Thanks in advance for any help! >>> >>> Best regards, >>> >>> Charles Novaes de Santana >>> -- >>> Um axé! :) >>> >>> -- >>> Charles Novaes de Santana, PhD >>> http://www.imedea.uib-csic.es/~charles >>> >> > > > -- > Um axé! :) > > -- > Charles Novaes de Santana, PhD > http://www.imedea.uib-csic.es/~charles > -- Um axé! :) -- Charles Novaes de Santana, PhD http://www.imedea.uib-csic.es/~charles
