# QR decomposition in julia 2x slower than octave

**URL:** <https://discourse.julialang.org/t/qr-decomposition-in-julia-2x-slower-than-octave/10043>\
**Category:** Performance\
**Tags:** question\
**Created:** [March 28, 2018, 10:24pm UTC](https://discourse.julialang.org/t/qr-decomposition-in-julia-2x-slower-than-octave/10043 "2018-03-28T22:24:49Z")\
**Posts on this page:** 1\
**Showing post:** 6

<div class="post-metadata">

**Author:** ![PetrKryslUCSD](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/petrkryslucsd/32/215825_2.png) [@PetrKryslUCSD](https://discourse.julialang.org/u/PetrKryslUCSD)\
**Post date:** [March 28, 2018, 11:56pm UTC](https://discourse.julialang.org/t/qr-decomposition-in-julia-2x-slower-than-octave/10043/6 "2018-03-28T23:56:28Z")

</div>

Not so for Matlab:

```julia
>> A=rand(5000, 5000);
>> tic; qr(A); toc
Elapsed time is 4.189508 seconds.
>> version

ans =

    '9.4.0.813654 (R2018a)'

>> tic; [q,r]=qr(A); toc
Elapsed time is 5.785541 seconds.

```

---

_[View the full topic](https://discourse.julialang.org/t/qr-decomposition-in-julia-2x-slower-than-octave/10043)._