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From Apache Wiki <wikidi...@apache.org>
Subject [Hama Wiki] Trivial Update of "Architecture" by udanax
Date Tue, 17 Mar 2009 09:08:10 GMT
```Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Hama Wiki" for change notification.

The following page has been changed by udanax:
http://wiki.apache.org/hama/Architecture

------------------------------------------------------------------------------

==== The addition of multiple matrices ====
* https://issues.apache.org/jira/browse/HAMA-154
- === Dense Matrix-Matrix multiplication ===
+ === Matrix-Matrix multiplication ===

+ ==== Dense Matrices multiplication ====
To mutliply two dense matrices A and B, We collect the blocks to 'collectionTable' firstly
using map/reduce. Rows are named as c(i, j) with sequential number ((N^2 * i) + ((j * N) +
k) to avoid duplicated records.

{{{
@@ -52, +53 @@

}}}

- Each row has a two sub matrices of a(i, k) and b(k, j) so that minimized data movement and
network cost. Finally, We multiply and sum sequentially.
+ Each row has a two sub matrices of a(i, k) and b(k, j) so that minimized data movement and
network cost.

{{{
Blocking jobs:
@@ -73, +74 @@

-- ''If A stored on Hbase and we collect the B to A, Can we reduce the run time of blocking
job.  --Edward ''

+ ==== Sparse Matrices multiplication ====
+
+  * http://issues.apache.org/jira/browse/HAMA-127
+
- === Find the maximum absolute row sum of matrix ===
+ === Find the maximum absolute row sum of dense/sparse matrix ===

Matrix.Norm.One is that find the maximum absolute row sum of matrix. Comparatively, it's
a good fit with !MapReduce model because doesn't need iterative jobs or table/file JOIN operations.

@@ -91, +96 @@

=== Compute the infinity norm ===

- It's a maximum absolute column sum of matrix.
+ It's a maximum absolute column sum of dense/sparse matrix.

{{{
i=n
@@ -103, +108 @@

- Reduce task sum the absolute values of column, select the one maximum one.
}}}

- === Compute the transpose of a matrix ===
+ === Compute the transpose of dense/sparse matrix ===

The transpose of a matrix is another matrix in which the rows and columns have been reversed.
The matrix must be square for this work.

@@ -129, +134 @@

- Reduce task sets the reversed values
}}}

-
- === Compute the determinant of matrix ===
+ === Compute the determinant of square matrix ===

* http://issues.apache.org/jira/browse/HAMA-66

```
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