Can anyone please vectorize the code I have?

1 view (last 30 days)
Input
J_org =
0 2 0 1 0 -1 -1
2 0 0 -1 -1 3 0
0 0 0 -2 0 1 1
1 -1 -2 0 2 0 0
0 -1 0 2 0 0 1
-1 3 1 0 0 0 0
-1 0 1 0 1 0 0
J_upper = triu(J_upper);
J_indices = [ 0 1 0 2 0 3 4
0 0 0 5 6 7 0
0 0 0 8 0 9 10
0 0 0 0 12 0 0
0 0 0 0 0 0 13
0 0 0 0 0 0 0
0 0 0 0 0 0 0]
Output:
J_out =[ 2 1 -1 -1 -1 -1 3 -2 1 1 0 2 1 0]
output J_out should be a flattened 1D vector where J_out(J_indices ) should be corresponding value from J_upper. If a J_index is missing (for example, 11 and 14 in my example), the value of that J_out will be zero. Length(J_out) should be ceil(0.5*length(J_org)*max(degree(graph(J_org)))). Here is my version of the code:
J_out = zeros(1,ceil(0.5*length(J_org)*max(degree(graph(J_org)))));
for i = 1:length(J_org)
for j =1:length(J_org)
if J_indices(i,j)
J_out (J_indices(i,j))= J_upper(i,j);
end
end
end

Accepted Answer

Bruno Luong
Bruno Luong on 14 May 2022
Edited: Bruno Luong on 14 May 2022
There is nothing in your data to guess that Jout must have 14 elements, the last index > 0 is 13.
J_org = [
0 2 0 1 0 -1 -1
2 0 0 -1 -1 3 0
0 0 0 -2 0 1 1
1 -1 -2 0 2 0 0
0 -1 0 2 0 0 1
-1 3 1 0 0 0 0
-1 0 1 0 1 0 0]
J_org = 7×7
0 2 0 1 0 -1 -1 2 0 0 -1 -1 3 0 0 0 0 -2 0 1 1 1 -1 -2 0 2 0 0 0 -1 0 2 0 0 1 -1 3 1 0 0 0 0 -1 0 1 0 1 0 0
J_upper = triu(J_org);
J_indices = [ 0 1 0 2 0 3 4
0 0 0 5 6 7 0
0 0 0 8 0 9 10
0 0 0 0 12 0 0
0 0 0 0 0 0 13
0 0 0 0 0 0 0
0 0 0 0 0 0 0]
J_indices = 7×7
0 1 0 2 0 3 4 0 0 0 5 6 7 0 0 0 0 8 0 9 10 0 0 0 0 12 0 0 0 0 0 0 0 0 13 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Jut=J_upper.';
Jit = J_indices.';
b=Jit>0;
Jout = zeros(1,14); % or J_out = zeros(1,ceil(0.5*length(J_org)*max(degree(graph(J_org)))))
Jout(Jit(b)) = Jut(b)
Jout = 1×14
2 1 -1 -1 -1 -1 3 -2 1 1 0 2 1 0
  2 Comments
Bruno Luong
Bruno Luong on 14 May 2022
@Nadatimuj You are welcome, if it helps could you accept the answer?

Sign in to comment.

More Answers (0)

Products


Release

R2021b

Community Treasure Hunt

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

Start Hunting!

Translated by