# Removing a row from a matrix based on certain conditions

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Yaser Khojah on 26 Jan 2019
Commented: Yaser Khojah on 26 Jan 2019
I have three variables t_SS, t_A, and G and all of them have the size of 10000 X 8. I'm looking for away to remove the entire row in G if any of the following coniditions is met. Below is my code and does not work properly since if G is deleted in the first conidtion, the number of index change.
Not sure how to fix it and thanks in advance.
Index_N_tS = find(t_SS < 0);
Index_N_tA = find(t_A < 0);
Index_less_A = find(t_A < t_SS);
I have to check these cells are not empty:
indx1_tS = isempty(Index_N_tS);
indx1_tS = isempty(Index_N_tS);
indx3_tA = isempty(Index_less_A)
% if any of the condition is met, remove the entire row in G
if indx1_tS == 0
G(Index_N_tS ,:) = [];
end
if indx2_tA == 0
G(Index_N_tA,:) = [];
end
if indx3_tA == 0
G(Index_less_A,:) = [];
end
Thank you

Stephen23 on 26 Jan 2019
Edited: Stephen23 on 26 Jan 2019
You do not explain how you want to handle the 8 columns in your logical comparisons: do you only want to remove the entire row if any column meets that condition, or if all columns meet that condition?
Here is a solution that works for any column meeting those conditions:
idx = any(t_SS < 0 | t_A < 0 | t_A < t_SS, 2);
G(idx,:) = []
You will need to decide if any or all or some other column handling is what you need.
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Yaser Khojah on 26 Jan 2019
Thank you so much Stephen for your help :)