Applying the Send/receive Programming Model as Outlined in the Example

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The Answer is As in the example, we first need to distribute the subsets to the 10 processor-memory nodes. The processor with the 50x50 matrix will first send them. This will entail sending equal matrix chunks. One possible division is sending 50x5 matricies to each of the 10. It is important that the processor know which chunk it has received if you re-merge recursively as the reduction sum in the example (code omitted in example, also omitted here).
The next step is to perform the scalar multiplication on our subset. Assuming division and send as stated before and that we have received our chunk of the matrix as A, code:
for(i = 0; i < 50; i++) for(j = 0; j < 5; j++)
A[i][j] *= c;
The final step is to collect each partial matrix back into the original matrix. We can do this either using the scheme presented in the example where half of processors send their chunks to the other half recursively. We must, however, also note to the receiving processor which portion of the complete array we have operated on, or have knowledge of where data from processor n is to fit in the complete array so that it can be merged correctly. An alternative method for this 10 processor example would be to send the array chunk back to the initiating processor for the merge.

Applying the Send/receive Programming Model as Outlined in the Example

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