# Sum of the elements of rows of matrix

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Akmyrat on 28 May 2014
Commented: Jos (10584) on 29 May 2014
lets say i have A=[1 2 1;3 2 1;3 5 4] and i want to sum up row elements separately and show me results as "Ri=..." here "i" is number of row. in this case R1=7, R2=9. R3=6.
Matt J on 28 May 2014
It sounds like you really mean "sum up column elements". The elements you are summing all belong to a common column, not a common row.

Matt J on 28 May 2014
Edited: Matt J on 28 May 2014
Asum=sum(A,1);
for i=1:length(Asum)
disp(['R' num2str(i) '=' num2str(Asum(i))]);
end
Jos (10584) on 29 May 2014
:-) Indeed, you exactly did what Akmyrat asked for ...

Chandrasekhar on 28 May 2014
sum(A')
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Chandrasekhar on 28 May 2014
Please let us know what is best way to do this?

Jos (10584) on 28 May 2014
You do not want to store the results in separate variables R1, R2, etc., but rather as elements of a single variable R, with R(1), R(2), etc.
A = magic(3)
RowSum = sum(R,2)
help sum
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Jos (10584) on 28 May 2014
What do you mean, "not working"? Did you read the help of sum?
May be you want to sum along rows rows, i.e., sum the elements in each column?
ColumnSum = sum(R,1)
Next time, be a little bit more specific ...