### Author:  [@findmyway](https://discourse.julialang.org/u/findmyway)
#### Post date: [May 13, 2019, 4:20pm UTC](https://discourse.julialang.org/t/how-to-set-the-seed-properly-in-curand/24180/1 "2019-05-13T16:20:12Z")
I just found it’s a little tricky for me to set the seed in `CuArrays.CURAND`
```julia
julia> using CuArrays, CuArrays.CURAND
julia> s = CuArrays.CURAND.create_generator()
CuArrays.CURAND.RNG(Ptr{Nothing} @0x00000000054faec0, 100)
julia> rand(s, Float32, 3)
3-element CuArray{Float32,1}:
0.74021935
0.9209938
0.03902049
julia> rand(s, Float32, 3)
3-element CuArray{Float32,1}:
0.9689629
0.92514056
0.4463501
```
Obviously, setting the same seed `s` doesn’t work.
After reading the source code, I found there’s a function named `set_pseudo_random_generator_seed`:
```julia
julia> CuArrays.CURAND.set_pseudo_random_generator_seed(s, 123)
0x00000000
julia> rand(s, Float32, 3)
3-element CuArray{Float32,1}:
0.048817795
0.57627815
0.8071622
julia> CuArrays.CURAND.set_pseudo_random_generator_seed(s, 123)
0x00000000
julia> rand(s, Float32, 3)
3-element CuArray{Float32,1}:
0.036559016
0.5210836
0.61308384
```
Still not working.
After googling I found this answer:
>
And yes, it seems works!
```julia
julia> CuArrays.CURAND.set_generator_offset(s, 0)
0x00000000
julia> rand(s, Float32, 3)
3-element CuArray{Float32,1}:
0.48431787
0.40131402
0.79087174
julia> CuArrays.CURAND.set_generator_offset(s, 0)
0x00000000
julia> rand(s, Float32, 3)
3-element CuArray{Float32,1}:
0.48431787
0.40131402
0.79087174
```
I’m not very familiar with CURAND. Can anyone help to point out why I need to call `set_generator_offset` here (is it the right way to do so)? And what’s the meaning of `set_pseudo_random_generator_seed`?
Found another resource. Hope it is useful for someone else.
> **[Creating Randomness and Acummulating Change](https://richiesams.blogspot.com/2015/03/creating-randomness-and-acummulating.html)**
>
> This is the second post in a series documenting my adventures in creating a GPU path tracer from scratch. If you missed it, the first post i...
---
### Author:  [@c42f](https://discourse.julialang.org/u/c42f)
#### Post date: [May 14, 2019, 9:04am UTC](https://discourse.julialang.org/t/how-to-set-the-seed-properly-in-curand/24180/2 "2019-05-14T09:04:11Z")
The curand documentation explains the offset briefly:
[https://docs.nvidia.com/cuda/curand/host-api-overview.html#generator-options](https://docs.nvidia.com/cuda/curand/host-api-overview.html#generator-options)
To get the same random numbers you’d need the same seed and the same offset, as you’ve found. The seed defines the sequence, and the offset allows you to skip to a point in the sequence.
It does seem a bit surprising that setting the seed doesn’t also reset the offset to zero.
---
### Author:  [@Ferran\_Mazzanti](https://discourse.julialang.org/u/Ferran_Mazzanti)
#### Post date: [November 15, 2019, 8:53am UTC](https://discourse.julialang.org/t/how-to-set-the-seed-properly-in-curand/24180/3 "2019-11-15T08:53:10Z")
Hi,
is this still working for you? In my case, the very first line
```julia
using CuArrays, CuArrays.CURAND
s = CuArrays.CURAND.create_generator()
```
spits
```julia
UndefVarError: create_generator not defined
Stacktrace:
[1] getproperty(::Module, ::Symbol) at ./Base.jl:13
[2] top-level scope at In[14]:2
```
so I can not initialize my random numboos ☹
But I’m 100% sure I’m missing something, so any help will be much appreciated.
BTW my CuArrays etc things are working well on my Julia 1.2.0 boxes… pretty well I must say! More than 100 times faster that usual Julia, which I start to seriously believe is not that fast as people claims…
Thanks in advance,
Ferran.
---
### Author:  [@maleadt](https://discourse.julialang.org/u/maleadt)
#### Post date: [November 15, 2019, 8:55am UTC](https://discourse.julialang.org/t/how-to-set-the-seed-properly-in-curand/24180/4 "2019-11-15T08:55:41Z")
@findmyway made a PR that puts these calls in `seed!`, so there’s no need to call internal methods anymore: [https://github.com/JuliaGPU/CuArrays.jl/pull/344](https://github.com/JuliaGPU/CuArrays.jl/pull/344).
---
### Author:  [@Ferran\_Mazzanti](https://discourse.julialang.org/u/Ferran_Mazzanti)
#### Post date: [November 15, 2019, 4:04pm UTC](https://discourse.julialang.org/t/how-to-set-the-seed-properly-in-curand/24180/5 "2019-11-15T16:04:49Z")
Oh, thanks, that now works as expected.
May I tell you that you guys are doing a great work with this CUDA ports to Julia? It’s been the first time that I can do real and useful CUDA programming without feeling it it a big mess 🙂