I have to switch the max and min elements in a vector and assume vec = ceil(rand(1, 10)*100) is a vector containing 10 random generated integers. The script i have to provide will swap the maximum and the minimum element in the vector.

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I don't even know where to start, any help? Example: vec=[ 16 98 96 49 81 15 43 92 80 96], you script will result in vec = [ 16 15 96 49 81 98 43 92 80 96]

Answers (3)

ANKUR KUMAR
ANKUR KUMAR on 28 Sep 2018
Edited: ANKUR KUMAR on 28 Sep 2018
Firstly, please follow Walter Roberson's comment.
A=[ 16 98 96 49 81 15 43 92 80 96]
A([find(A==min(A)),find(A==max(A))])=ones(1,length(find(A==min(A))))*max(A),ones(1,length(find(A==max(A))))*min(A)]
  5 Comments
ANKUR KUMAR
ANKUR KUMAR on 28 Sep 2018
Oh sorry. I forgot to take this into consideration. This will work.
A = [1, 3, 2, 1, 10]
A([find(A==min(A)),find(A==max(A))])=[ones(1,length(find(A==min(A))))*max(A),ones(1,length(find(A==max(A))))*min(A)]

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Bruno Luong
Bruno Luong on 28 Sep 2018
Solution for the problem of "swapping" ties min-values with ties max-values
minA = min(A);
maxA = max(A);
ismax = A==maxA;
A(A==minA) = maxA;
A(ismax) = minA;

Stephen23
Stephen23 on 28 Sep 2018
Edited: Stephen23 on 28 Sep 2018
Even though this is homework without any attempt... here is a neat and efficient MATLAB way to do that (this swaps the first minimum and the first maximum):
>> vec = [16,98,96,49,81,15,43,92,80,96]
vec =
16 98 96 49 81 15 43 92 80 96
>> [~,idn] = min(vec);
>> [~,idx] = max(vec);
>> vec([idn,idx]) = vec([idx,idn])
vec =
16 15 96 49 81 98 43 92 80 96
Of course you cannot hand this in as your own work, because that would be plagiarism.
  3 Comments
Bruno Luong
Bruno Luong on 28 Sep 2018
Edited: Bruno Luong on 28 Sep 2018
But your (Ankur's) code and Stephen's code do not perform the same arrangement in the case of tie. And poster never specify which one he actually needs.
Stephen23
Stephen23 on 28 Sep 2018
Edited: Stephen23 on 28 Sep 2018
Swap all tied maximum/minimum values:
>> vec = [15,16,96,96,49,81,15,43,92,80,96]
vec =
15 16 96 96 49 81 15 43 92 80 96
>> idn = find(min(vec)==vec);
>> idx = find(max(vec)==vec);
>> vec([idn,idx]) = vec([idx(1)*ones(1,numel(idn)),idn(1)*ones(1,numel(idx))])
vec =
96 16 15 15 49 81 96 43 92 80 15

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