Insert NaNs (or any value) in several position of a vector

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Hi i have a vector like this
a=[1 2 3 5 6 7 9 10 13 14];
I would like to find where the diff is bigger than a value (let's say one) and insert a NaN between the two positions. I need this to plot a discontinuous line that is interrupted if the X value grows too much.
I tried something like
ind=diff(a)>1
for i=1:length(a)
if ind(i)
a=[a(1:i),NaN,a(i+1:end)]
end
end
the problem is that whenever I add a NaN the followig value of a get shifted by one positiona and the positions in ind are no longer valid. I could shift ind too or I could copy each value of a into b adding NaN etc etc...
But they all seems over complicated method. Anyone got a good idea on how to do it?
thanks

Accepted Answer

the cyclist
the cyclist on 11 Sep 2015
Here is one way:
a=[1 2 3 5 6 7 9 10 13 14];
insertNanIndex = [0 diff(a)>1];
insertValue = (1-insertNanIndex)./0;
b_tmp = [a; insertValue];
b = b_tmp(:)';
b(isinf(b)) = [];
Notice that I temporarily fill in "Inf", and then extract it. So, if your original dataset has "Inf" in it, you will need to do a different dummy var.
  1 Comment
Luca Amerio
Luca Amerio on 11 Sep 2015
SMART!
I have to correct the row
b_tmp = [insertValue; a];
otherwise it insert the NaNs in the wrong position. But...WOW! Nice way to do it!

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More Answers (1)

Juliana Damaceno
Juliana Damaceno on 23 Jan 2019
If the jump is one followed by the other this way do not work :(

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