how to delete a row from a matrix

2 views (last 30 days)
nadia nadi
nadia nadi on 25 Oct 2015
Edited: Stephen23 on 25 Oct 2015
Dear,
I need to delete rows with all zeros from B and corresponding ones from b, where Bx>=b, so I wrote this code but I got error because of the index, can anyone check it for me please and if there is any faster way will be very helpful. Thanks in advance.
Nadia
B=[
1 0 0 0 0 0 0
0 0 0 1 0 0 0
0 0 0 0 0 0 0
0 1 0 1 0 0 0
0 0 0 0 1 1 0
0 1 0 0 0 0 1
0 0 0 0 0 0 0
0 0 0 0 0 0 1
0 0 1 0 0 0 0];
b=ones(size(B,1),1);
for i=1:size(B,1)
while B(i,:)==0
B(i,:)=[]
b(i,:)=[]
end
end
  1 Comment
Jan
Jan on 25 Oct 2015
The error is caused by running the for i loop until the original size of B, but B has been shortend already inside the loop.

Sign in to comment.

Accepted Answer

Stephen23
Stephen23 on 25 Oct 2015
Edited: Stephen23 on 25 Oct 2015
When you use vectorized code then this task is simple, and there is no need for complicated loops:
>>B(any(B,2),:)
ans =
1 0 0 0 0 0 0
0 0 0 1 0 0 0
0 1 0 1 0 0 0
0 0 0 0 1 1 0
0 1 0 0 0 0 1
0 0 0 0 0 0 1
0 0 1 0 0 0 0
  1 Comment
nadia nadi
nadia nadi on 25 Oct 2015
Edited: nadia nadi on 25 Oct 2015
Dear Stephen,
That's great, thanks a lot.
Nadia

Sign in to comment.

More Answers (0)

Categories

Find more on Matrices and Arrays in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!