# How to change Elements in Matrix per row depending on their size in reference to a particular Element (without loop)

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Tim on 14 Feb 2014
Answered: Jos (10584) on 18 Feb 2014
I've Data (in the real case much bigger) like this: A =
0 3 4 5 2 3 1
2 4 6 2 1 6 8
1 1 1 3 2 1 8
4 4 3 3 1 0 0
2 3 2 2 1 9 0
Not I want to change elements in different rows if they are bigger than a particular number: For example in Row 1,3,4 there should not be an Element bigger then 3 and in Row 2,5 there should not be an Element larger then 2.
So the Result should look like: A =
0 3 3 3 2 3 1
2 2 2 2 1 2 2
1 1 1 3 2 1 3
3 3 3 3 1 0 0
2 2 2 2 1 2 0
I tried to solve the Problem like this but it doesnt work:
A(A([1 3 4],:)>=3)=3
A(A([2 5],:)>=2)=2
Does someone have a good solution or does anyone know where my mistake is?

Azzi Abdelmalek on 14 Feb 2014
Edited: Azzi Abdelmalek on 14 Feb 2014
B=A([ 1 3 4],:);
B(B>3)=3
A([1 3 4],:)=B
B=A([ 2 5],:);
B(B>2)=2
A([2 5],:)=B
Tim on 18 Feb 2014
Thanks, that helped!

Jos (10584) on 18 Feb 2014
The easy way:
A([1 3 4],:) = min(A([1 3 4],:),3) ;
A([2 5],:) = min(A([2 5],:),2) ;

Thomas on 14 Feb 2014
A laborious way of doing it..
B=[A(1,:);A(3,:);A(4,:)];
B(B >=3)=3;
C=[A(2,:);A(5,:)];
C(C >=2)=2;
Out=[B(1,:);C(1,:);B(2,:);B(3,:);C(2,:)]
Of course there are gonna be better ways of doing this.. ;)
Tim on 18 Feb 2014
Thanks!