# Spit an array when the value 0 occurs until the value 2

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Fabio Taccaliti on 29 Jun 2022
Commented: Walter Roberson on 30 Jun 2022
I have an array time (6700x1) containing all numbers from -8 to 5 in ascending order.
I would like to have a new array (time_new) based on this that contains all value between 0 and 2.
I know that I can just open the array and look at which position the value 0 occurs and at wich index the value 2 and based on this do time(3981:4962). But since I'm dealing with several arrays where the position of these 2 numbers is not always the same I would like to have something more roboust that I can always use without every time open the array and look for the teo index.
Can someone help to with that?
Dyuman Joshi on 29 Jun 2022
Why do you think finding the position and using the index is not a robust method?
Use logical indexing then. (as @Voss has answered)

Voss on 29 Jun 2022
% an array time (6700x1) containing numbers from
% -8 to 5 in ascending order:
time = linspace(-8,5,6700).'
time = 6700×1
-8.0000 -7.9981 -7.9961 -7.9942 -7.9922 -7.9903 -7.9884 -7.9864 -7.9845 -7.9825
% time_new based on this that contains
% all value between 0 and 2:
time_new = time(time >= 0 & time <= 2) % use >, < if you want to exclude 0, 2
time_new = 1031×1
0.0010 0.0030 0.0049 0.0069 0.0088 0.0107 0.0127 0.0146 0.0166 0.0185
Voss on 30 Jun 2022
You're welcome!

Walter Roberson on 29 Jun 2022
Your request is a bit ambiguous, so I will give two possibilities.
loc0 = find(YourArray == 0, 'first');
%use this
loc2F = find(YourArray == 2, 'first');
subsetF = YourArray(loc0:loc2F-1);
%OR use this
loc2L = find(YourArray == 2, 'last');
subsetL = YourArray(loc0:loc2L);
Now subsetF includes from the first 0 to the last value before the 2. subsetL includes from the first 0 to the last 2. You do not need both of these; I am just not clear which one you want.
Note that this code is not designed to work if there are no 0 or there are no 2.
Walter Roberson on 30 Jun 2022
loc0 = find(YourArray == 0, 1, 'first');
%use this
loc2F = find(YourArray == 2, 1, 'first');
subsetF = YourArray(loc0:loc2F-1);
%OR use this
loc2L = find(YourArray == 2, 1, 'last');
subsetL = YourArray(loc0:loc2L);

R2022a

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