huh.

maybe @everywhere in front of the function definition? I'm not sure


On Tue, Feb 4, 2014 at 10:53 AM, Alex C <[email protected]> wrote:

> Thanks for the hint. Getting rid of 'mx' and 'my' definitely helps.
>
> I couldn't figure out how to implement the parallel version of tuple
> adding. This is what I've got. It crashes my Julia Studio console when I
> try to run it. What am I missing?
>
> add_two_tuple(x,y) = (x[1]+y[1], x[2]+y[2], x[3]+y[3])
>
>
> @parallel (add_two_tuple) for i = 1:100
>
>     x = (1,2,3)
>
> end
>
>
> I also don't have the SharedArray function (running Julia 0.2.0) so I
> couldn't implement the other alternative.
>
> Alex
>
>
> On Monday, February 3, 2014 11:45:57 AM UTC-5, David Salamon wrote:
>
>> You're not out of the no-slicing woods yet. Looks like you can get rid of
>> `mx` and `my`
>>
>> for i=1:limit, j=1:int64(limit/2)
>> end
>>
>>
>>
>> As far as parallelizing, you could define:
>> three_tup_add(a, b, c) = (a[1] + b[1] + c[1], a[2] + b[2] + c[2], a[3] +
>> b[3] + c[3])
>>
>> and then do a @parallel (three_tup_add) over your sample index?
>>
>> for that matter, why not compute the two parts of the answer directly
>> rather than going via A, B, and C?
>>
>>
>>
>>
>>
>>
>> On Mon, Feb 3, 2014 at 8:11 AM, Alex C <[email protected]> wrote:
>>
>>> Thanks. I've re-written the function to minimize the amount of copying
>>> (i.e. slicing) that is required. But now, I'm befuddled as to how to
>>> parallelize this function using Julia. Any suggestions?
>>>
>>> Alex
>>>
>>> function expensive_hat(S::Array{Complex{Float64},2},
>>> mx::Array{Int64,2}, my::Array{Int64,2})
>>>
>>>     samples = 64
>>>         A = zeros(size(mx));
>>>     B = zeros(size(mx));
>>>     C = zeros(size(mx));
>>>
>>>     for i = 1:samples
>>>         Si = S[:,i];
>>>         Sx = Si[mx];
>>>         Sy = Si[my];
>>>         Sxy = Si[mx+my];
>>>         Sxyc = conj(Sxy);
>>>
>>>                 A +=  abs2(Sy .* Sx);
>>>         B += abs2(sqrt(Sxyc .* Sxy));
>>>         C += Sxyc .* Sy .* Sx;
>>>     end
>>>
>>>         ans = (A .* B ./ samples ./ samples, C./samples)
>>>     return ans
>>>
>>> end
>>>
>>> data = rand(24000,64);
>>> limit = 2000;
>>>
>>> ix = int64([1:limit/2]);
>>> iy = ix[1:end/2];
>>> mg = zeros(Int64,length(iy),length(ix));
>>> mx = broadcast(+,ix',mg);
>>> my = broadcast(+,iy,mg);
>>> S = rfft(data,1)./24000;
>>>
>>> @time (AB, C) = expensive_hat(S,mx,my);
>>>
>>>
>>
>>

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