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It was in mid of a study (not related to Mathematics) I came across this equation:

enter image description here

I am not able to decode this expression. Here Zij refers to the values of a square matrix of nxn order.

Seeking help! Thanks in advance! :-)

1 Answers 1

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$\sum_{j=1}^n |z_{ij}|$ is the sum of the absolute values of the elements in row $i$ of the matrix.

$\max_{1 \le i \le n} \sum_{j=1}^n |z_{ij}|$ is the maximum across all rows of those sums.

The second term probably has a typo (the $i$ in $\max$ should be a $j$). It most likely meant to be : $\;\max_{1 \le j \le n} \sum_{i=1}^n |z_{ij}|\;$ i.e. the maximum across all columns of the sum of the absolute values of the elements in column $j$ of the matrix.

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    Sorry If I am going wrong here somehow but why is it "n times" because there is no "n" between max1≤i≤n and ∑nj=1|zij| in the image. Isn't it just "maximum across all rows of those sums" – 2017-01-16
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    @VishalKNair Thanks for pointing, I had misread that. Edited and fixed. – 2017-01-16