# How to deal with Index exceeds the number of array elements ?

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Tomaszzz on 31 Jan 2022
Answered: Ankit on 31 Jan 2022
Hi all,
I have a signal like this (also attached).
I want to extract signal between first start and first end, second start and second end and so on. I am doing this like this:
start_location = [147,222,302,379,458,538,620,698,777];
start_value = [-81.905,-87.408,-86.262,-85.463,-85.893,-84.910,-84.614,-83.543,-84.500]
end_location = [200,275,352,431,511,593,674,762];
end_value = [-85.369,-85.028,-82.240,-80.933,-80.943,-80.082,-83.108,-85.543];
plot(thigh_orient_y,'k')
hold on
plot(start_location,start_value,'ro')
plot(end_location,end_value,'g*')
h = legend('signal','start', 'end');
%Settings
a = start_location ;
b = end_location;
n = length(a);
%Extract data between red and green indices and put in cells
T_or_y_cycle = cell(n,1) ;
for i = 1:n
T_or_y_cycle{i} = thigh_orient_y(a(i):b(i)) ;
end
I am getting error
Index exceeds the number of array elements
Beacuse there is larger number of 'start' than 'end', as the signal is cut at the end. Can you please help how to deal with this?
The n cannot be lenght(b) beacuse the signal can be cut at the begging and start with 'end' like here:
##### 2 CommentsShowHide 1 older comment
Tomaszzz on 31 Jan 2022
Edited: Tomaszzz on 31 Jan 2022
Thanks, this does the trick, how can I accept you answer?

Ankit on 31 Jan 2022
start_location = [147,222,302,379,458,538,620,698,777];
start_value = [-81.905,-87.408,-86.262,-85.463,-85.893,-84.910,-84.614,-83.543,-84.500]
end_location = [200,275,352,431,511,593,674,762];
end_value = [-85.369,-85.028,-82.240,-80.933,-80.943,-80.082,-83.108,-85.543];
plot(thigh_orient_y,'k')
hold on
plot(start_location,start_value,'ro')
plot(end_location,end_value,'g*')
h = legend('signal','start', 'end');
%Settings
a = start_location ;
b = end_location;
n = min(length(a),length(b)); % this will avoid extra start or end value.
%Extract data between red and green indices and put in cells
T_or_y_cycle = cell(n,1) ;
for i = 1:n
T_or_y_cycle{i} = thigh_orient_y(a(i):b(i)) ;
end

KSSV on 31 Jan 2022
Your start_location is of size 1x9. Where as end_location is only 1x8. You need to put one more index in the variable end_location.

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