[Hama Wiki] Update of "MatrixNorm" by Edward J. Yoon

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The "MatrixNorm" page has been changed by Edward J. Yoon.
http://wiki.apache.org/hama/MatrixNorm

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New page:
==== Matrix Norm ====

In examples package of Hama, we have introduced !MapReduce-based computing methods for matrix norms.

 * Maximum absolute column sum
 * The root of sum of the sum of squares
 * The maximum absolute row sum
 * Largest entry in absolute value

Here's the example one of them. Matrix.Norm.One is that find the maximum absolute row sum of matrix. 

{{{

                                         j=n
The maximum absolute row sum =   max   ( sum | a_{i,j} | ) 
                               1<=i<=n   j=1


- A map task receives a row n as a key, and vector of each row as its value
  - emit (row, the sum of the absolute value of each entries)
- Reduce task select the maximum one
}}}

Matrix.infinity, Matrix.Maxvalue and Matrix.Frobenius are almost same with this.