parallel computing-- sharing viable between threads

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Hi, recently, I am working on a project that needs parallel computing. I already know things like parfor. However, the difficulty in this project is that, it requires sharing a global variable between threads. For example, if there are two threads both computing "a=a+1;"in a for loop, than the parfor results should be "lab1 : 1,2,3,4,5,6...; lab2 : 1,2,3,4,5,6...", what I expect is probably like this:"lab1: 1,3,6,7,9... lab2: 2,4,5,8,10...." which two threads are both changing the same variable (It doesn't care the sequence of which thread does the add, as long as all threads are adding the number together) Can anybody help me with that?

Answers (1)

Walter Roberson
Walter Roberson on 16 Mar 2017
It is not possible to have a global shared between workers.
You can use spmd to labSend and labReceive
As of the newly released r2017a there is the ability to send between workers. I would need to check the details.
You might be able to benefit from the sharedmatrix file exchange contribution
  2 Comments
yu liu
yu liu on 16 Mar 2017
Hi, Roberson. Thanks for reply, I'll check that
Walter Roberson
Walter Roberson on 16 Mar 2017
The new facilities in R2017a are send(), poll(), and afterEach(). However, these facilities are to transfer data back and forth between the client and the workers, and are not for transferring data between workers: to transfer between workers, spmd with labSend() and labReceive() is still the mechanism.

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