array with 1 and -1 - multiply coloums
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Hello,
I have an array with a lot of -1 and 1.
Example:
-1 -1 -1 -1 -1
-1 1 -1 -1 -1
1 1 -1 1 -1
-1 -1 1 1 -1
I want to check if the row has 1 and if so if it has more than one 1. If I have more than one 1 in a row I want to multiply the columns for each row with a 1 and write the result into an new array.
For example:
The first row has no 1 > write in the new array 0
The second row has just one 1 in the second column > write the second column into a new array
The third row has a one in the first, second and fourth column > mulitply the three coloums and write the result into the new array
...
Thanks in advance for the answers!
3 个评论
Jan
2022-11-2
What is the wanted output for the posted input? 1 matrix or 3 vectors?
What have you tried so far and which problems occur?
Ma Hel
2022-11-3
Jan
2022-11-3
I assume the problem is solved by Voss' answer. But for your next question: It would be really helpful, if you do not only mention, that it is "one matrix" but post the manually created output for the shown input.
采纳的回答
Like this?
M = [
-1 -1 -1 -1 -1
-1 1 -1 -1 -1
1 1 -1 1 -1
-1 -1 1 1 -1];
[n,m] = size(M);
new_arrays = repmat({zeros(n,1)},1,n);
for ii = 1:n
idx = M(ii,:) == 1;
if any(idx)
new_arrays{ii} = prod(M(:,idx),2);
end
end
new_arrays{:}
2 个评论
Ma Hel
2022-11-3
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