Re: [julia-users] linear algebra speed comparisons with MATLAB

2014-05-23 Thread Andreas Noack Jensen
Unfortunately, it is not that clear cut. In the thread I linked you can see some discussion and timings. It is correct that OpenBLAS is faster for large problems, but it is slower for small problems. 2014-05-22 23:17 GMT+02:00 Thomas Covert : > By the way, switching to Homebrew and compiling a r

Re: [julia-users] linear algebra speed comparisons with MATLAB

2014-05-22 Thread Thomas Covert
By the way, switching to Homebrew and compiling a recent git pull solved the problem. Now my matrix inversions occur at MATLAB speeds or faster. On Monday, May 19, 2014 7:58:06 AM UTC-5, Andreas Noack Jensen wrote: > > Thanks. Julia is calling the correct method. > > However, I didn't read your

Re: [julia-users] linear algebra speed comparisons with MATLAB

2014-05-19 Thread Andreas Noack Jensen
Thanks. Julia is calling the correct method. However, I didn't read your last email carefully enough. You are pointing to the problem. The pre-build binary for Mac does not use OpenBLAS but Apple's Accelerate which apparently is slower. I have filed an issue https://github.com/JuliaLang/julia/iss

Re: [julia-users] linear algebra speed comparisons with MATLAB

2014-05-19 Thread Thomas Covert
Here's what I get: julia> K = randn(2500,2500); julia> K = K' * K; julia> @which inv(lufact(K)) inv{T<:Union(Float64,Complex{Float64},Complex{Float32},Float32),S<:Union(DenseArray{T,2},SubArray{T,2,A<:DenseArray{T,N},I<:(Union(Range{Int64},Int64)...,)})}(A::LU{T<:Union(Float64,Complex{Float64},C

Re: [julia-users] linear algebra speed comparisons with MATLAB

2014-05-19 Thread Andreas Noack Jensen
In generaI, I don't think most people experience that MKL is faster that OpenBLAS. On my MacBook, Julia with OpenBLAS and Matlab performs very similar on the symmetric inversion problem. Some time ago, there used to be a problem with inv falling back on a slower method. I should be fixed now, but

Re: [julia-users] linear algebra speed comparisons with MATLAB

2014-05-18 Thread Thomas Covert
Thanks for sending that along - might go down that route once it's clear that MKL would do the trick and that the fixed costs of building it myself are worth it. Are there other mac users using the pre-built binaries that see these same performance differences? Why do the mac binaries report libg

Re: [julia-users] linear algebra speed comparisons with MATLAB

2014-05-18 Thread Leah Hanson
There are instructions in the Julia README and on Intel's website for running Julia with MKL: https://github.com/JuliaLang/julia#intel-math-kernel-libraries https://software.intel.com/en-us/articles/julia-with-intel-mkl-for-improved-performance -- Leah On Sun, May 18, 2014 at 3:59 PM, Thomas Co

Re: [julia-users] linear algebra speed comparisons with MATLAB

2014-05-18 Thread Thomas Covert
Seems like the windows and Mac versions of Julia call different blas/lapack routines. Might that be the cause? Is it possible for me to ask julia to use a different blas/lapack? On Sunday, May 18, 2014, J Luis wrote: > Funny, in a similar machine (but running Windows) I get the opposite > > Ma

[julia-users] linear algebra speed comparisons with MATLAB

2014-05-18 Thread Thomas Covert
I am finding that MATLAB is considerably faster than Julia for simple linear algebra work on my machine (mid-2009 macbook pro). Why might this be? Is this an OpenBLAS vs Intel MKL issue? For example, on my machine, matrix inversion of a random, symmetric matrix is more than twice as fast in M