# non zero elements in an array

4 views (last 30 days)
ali hassan on 12 Feb 2022
Edited: Matt J on 13 Feb 2022
if a=[1 2 4 5 3 0 0 8 0]
how can i make the elements greater than or equal to 2 as 1 and smaller than two as 0.
so that it become like this:
[0 1 1 1 1 0 0 1 0]

Arif Hoq on 12 Feb 2022
a=[1 2 4 5 3 0 0 8 0];
[idx]=find(a<2);
a(idx)=0;
out=a;
[idx2]=find(out>=2);
out(idx2)=1
out = 1×9
0 1 1 1 1 0 0 1 0
Matt J on 13 Feb 2022
Edited: Matt J on 13 Feb 2022
but i got the concept which was required.
Except that this solution still teaches the regrettably popular habit of using find() in situations where it is unnecessary.
a=[1 2 4 5 3 0 0 8 0];
out=a;
out(a<2)=0;
out(a>=2)=1
out = 1×9
0 1 1 1 1 0 0 1 0

DGM on 12 Feb 2022
Edited: DGM on 12 Feb 2022
I'm going to assume you're only dealing in integers here, otherwise the question arises whether values between 1 and 2 should really be preserved.
a = [1.5 1 2 4 5 3 0 0 8 0];
b = max(min(a,1),0)
b = 1×10
1 1 1 1 1 1 0 0 1 0
If values between 1 and 2 should be preserved, then:
c = max(a,0);
c(c>=2) = 1
c = 1×10
1.5000 1.0000 1.0000 1.0000 1.0000 1.0000 0 0 1.0000 0

Matt J on 12 Feb 2022
Edited: Matt J on 13 Feb 2022
If a are always integers,
a = [1 2 4 5 3 0 0 8 0];
a=(a>=2)
a = 1×9 logical array
0 1 1 1 1 0 0 1 0