[julia-users] Re: matrix multiplication in Matlab is much faster

2016-10-16 Thread majid . zamani150
thanks @chris ... thanks a lot ...

On Sunday, October 16, 2016 at 8:51:56 PM UTC+3:30, Chris Rackauckas wrote:
>
> Take a look at the performance tips 
> . The 
> first time you run it, the function will compile. Then the compiled 
> function is cached. On my computer I did:
>
> a = rand(1000,1000)
> y=similar(a)
> @time a*a 
> @time a*a 
> @time A_mul_B!(y,a,a)
> @time A_mul_B!(y,a,a)
>
> Which gives output:
>
>
>   0.435561 seconds (367.13 k allocations: 20.108 MB, 1.58% gc time)
>   0.019922 seconds (7 allocations: 7.630 MB)
>
>   0.027144 seconds (53 allocations: 2.875 KB)
>   0.016211 seconds (4 allocations: 160 bytes)
>
> Notice how after compiling, the allocations and the timings go way down. 
> For a more in-depth look at how Julia is looking to get the speed (and how 
> to make the most of it), take a look at this blog post 
> . Julia is a 
> little bit more complex than MATLAB, but the payoffs can be huge once you 
> take the time to understand it. Happy Julia-ing!
>
>
> On Sunday, October 16, 2016 at 9:45:00 AM UTC-7, majid.z...@gmail.com 
> wrote:
>>
>> i have run the same matrix multiplication  in both matlab and julia but 
>> matlab in much faster that julia, i have used both A_mul_B! and *() 
>> functions
>> my codes are :
>> in matlab : 
>> tic 
>> a = rand(1000,1000)
>> a*a
>> toc
>> the output is : Elapsed time is 0.193979 seconds
>>
>> in Julia :
>> a = rand(1000,1000)
>> y=similar(a)
>> @time a*a 
>> @time A_mul_B!(y,a,a)
>>
>> the output is:
>> 1.575159 seconds
>> 1.497884  seconds
>> Majid
>>
>

[julia-users] matrix multiplication in Matlab is much faster

2016-10-16 Thread majid . zamani150
i have run the same matrix multiplication  in both matlab and julia but 
matlab in much faster that julia, i have used both A_mul_B! and *() 
functions
my codes are :
in matlab : 
tic 
a = rand(1000,1000)
a*a
toc
the output is : Elapsed time is 0.193979 seconds

in Julia :
a = rand(1000,1000)
y=similar(a)
@time a*a 
@time A_mul_B!(y,a,a)

the output is:
1.575159 seconds
1.497884  seconds
Majid