Unable to perform assignment because the size of the left side is 1-by-1 and the size of the right side is 1-by-0.

This is what i am trying to solve.

>> d = 1 2 3 4 5 6 7 8 9 10

>> dref = 3 5 7

>> A = % Creating from d of size (10x10) using (A = repmat(d, length(d),1))

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

1 2 3 4 5 6 7 8 9 10

>> B = % Taking only the lower traingle values from the diagonal.

1 0 0 0 0 0 0 0 0 0

1 2 0 0 0 0 0 0 0 0

1 2 3 0 0 0 0 0 0 0

1 2 3 4 0 0 0 0 0 0

1 2 3 4 5 0 0 0 0 0

1 2 3 4 5 6 0 0 0 0

1 2 3 4 5 6 7 0 0 0

1 2 3 4 5 6 7 8 0 0

1 2 3 4 5 6 7 8 9 0

1 2 3 4 5 6 7 8 9 10

using this;

B = zeros(length(d),length(d));

for i = 1:length(d)

B(i,1:i) = d(1):d(i);

end

* This is what i have already done. Now i want two matrices out of "B" matrix.

matrix C = containing all the diagonal values of B, and the values of "dref" in each row.

example, C =

1 0 0 0 0 0 0 0 0 0

0 2 0 0 0 0 0 0 0 0

0 0 3 0 0 0 0 0 0 0

0 0 3 4 0 0 0 0 0 0

0 0 3 0 5 0 0 0 0 0

0 0 3 0 5 6 0 0 0 0

0 0 3 0 5 0 7 0 0 0

0 0 3 0 5 0 7 8 0 0

0 0 3 0 5 0 7 0 9 0

0 0 3 0 5 0 7 0 0 10

matrix D = containing all the values of matrix B, without the diagonal elements and the "dref" values in each row.

example, D =

0 0 0 0 0 0 0 0 0 0

1 0 0 0 0 0 0 0 0 0

1 2 0 0 0 0 0 0 0 0

1 2 0 0 0 0 0 0 0 0

1 2 0 4 0 0 0 0 0 0

1 2 0 4 0 0 0 0 0 0

1 2 0 4 0 6 0 0 0 0

1 2 0 4 0 6 0 0 0 0

1 2 0 4 0 6 0 8 0 0

1 2 0 4 0 6 0 8 9 0

I have tried every method in my mind to solve it. But of no use. Just a hint would also suffice guys.

Thanks in advance.

[Rik]

What are you trying to achieve with the intersect function? It might not do what you think it does. You also don't index into dref, so your inner loop is pointless.

[Rahul Gulia]

I am trying to find the dref values in each outer loop

[Walter Roberson]

Look at your first value in dlink, which is 0. You intersect(0, dref) where dref is [7 3 6 6]. The intersection of those two sets is empty. You try to assign that emptiness to the definite location A(ii,p) . That is a mismatch on sizes, no values to assign but has to go into a place that has holds exactly one value.

I am trying to find the dref values in each outer loop

I do not understand that?

Are you trying to find the dlink values that are members of dref? If so then without loops,

intersect(dlink, dref)

which would give you [3 5 7]. That would not appear to be useful, as it is going to be the same as unique(dref)

[Rahul Gulia]

I have edited my problem guys, to explain it in a much better way. Hope that helps.

Answer 1

[Rik]

This should do the trick:

%your inital code:
d = 1:10;
dref = [3 5 7];
A = repmat(d, length(d),1);
B = zeros(length(d),length(d));
for i = 1:length(d)
   B(i,1:i) = d(1):d(i);
end

%my code:
d = 1:10;
dref = [3 5 7];
A=repmat(reshape(d,1,[]),numel(d),1);
B=tril(A);

diagonal=B.*(eye(size(B)));
lower_part=B.*(1-eye(size(B)));

L=ismember(lower_part,dref);
lower_part(~L)=0;

C=lower_part+diagonal;
D=B-C;

[Rahul Gulia]

That worked. Thank you Rik..