How to replace some Number in row matrix with NaN

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I have a row vector like this
Y = [5 7 18 16 40 18 9 32 15 4 9 60 40 24 10 13];
What I want is to replace a number Y(i) with NaN if and only if its abs diff with Y(i-1) and Y(i+1) is greater than 10. if not the number remains as it was.
For instance abs(Y(4)-Y(5))=24 which is > 10 & abs(Y(5)-Y(6))=22 >10 therefore Y(5) = 40 has to be replaced with NaN
Y_new = [5 7 18 16 NaN 18 9 NaN NaN 4 9 NaN NaN Nan 10 13];
I have tried the follwing code and id didn't worked
clear
clc
Y = [5 7 18 16 40 18 9 32 15 4 9 60 40 24 10 13];
len = numel(Y);
A=Y;
start = 1;
for jj = 2 :len -1
if abs(Y(start)- Y(jj))<10
start=jj;
elseif abs(Y(start)- Y(jj))>10 && abs(Y(jj)- Y(jj+1))<10
Y(start)=NaN;
start = jj+1;
elseif abs(Y(start)- Y(jj))>10 && abs(Y(jj)- Y(jj+1))>10
Y(jj) = NaN;
start = jj+1;
else
end
end

Accepted Answer

Yared Daniel
Yared Daniel on 17 Jun 2021
I have solved it!
clear
Y = [5 7 18 16 40 18 9 32 15 4 9 60 40 24 10 13];
idx = find(abs(diff(Y))>10);
L = numel(idx);
Y_new=Y;
for i=1:L-1
if abs(idx(i)-idx(i+1))==1
Y_new(idx(i)+1) =NaN;
else
end
end

More Answers (1)

KSSV
KSSV on 15 Jun 2021
Y = [5 7 18 16 40 18 9 32 15 4 9 60 40 24 10 13];
Y_new = [5 7 18 16 NaN 18 9 NaN NaN 4 9 NaN NaN NaN 10 13];
dY = diff([0 Y]) ;
idx = dY>10 ;
Y1 = Y ;
Y1(idx) = NaN ;
  3 Comments
KSSV
KSSV on 15 Jun 2021
Successive difference is considered. Your explanation is confusing. Try to extend the same logic to your case.
Yared Daniel
Yared Daniel on 15 Jun 2021
I have corrected the explanation to make clear

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