MATLAB Answers

How to Change element values of an array with conditions?

Latest activity Commented on by Fangjun Jiang
on 11 Nov 2019 at 2:16
If suppose, A=[2 3 4 7 9 10] i want to use if condition to add (e.g) 10 to the elements less than 6 (< 6) of array A, so that my array should convert into A=[12 13 14 7 9 10]. how can i achieve?

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2 Answers

Answer by Adam
on 31 Oct 2017
Edited by Adam
on 31 Oct 2017
 Accepted Answer

A( A < 6 ) = A ( A < 6 ) + 10
Sadly Matlab doesn't have a neat += operator so you have to do the above rather ugly equivalent, though I would often pull the logical indexing out into its own variable.

  3 Comments

Is there a similar solution for when you would like to alter in an interval within two limits, eg. adding 10 to each value between 4 and 6 in the array?
index=and(A>4,A<6);
A(index)=A(index)+10;

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Answer by Fangjun Jiang
on 31 Oct 2017

Play golf?
A=A+10*(A<6)

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I prefer this answer because you can assign the result of the operation to a different variable. Also works if you wanted to multiply instead of add:
S = A .* 10 .* (A < 6);

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