could anyone help me how to reshape the matrix.

I am having two matrices A=[3x2] and B=[1x2]

i want to reshape the size of A such that it should be equal to B,which mean A should contain only the first row.

could anyone please help me on this.

Answer 1

[John D'Errico]

You are not asking to do a reshape, which does not change the total number of elements.

A = A(1,:);

[jaah navi]

I tried with the following code:

B=[ 0.7684    0.0120;
    0.5333    0.9666;
    0.0684    0.8322;
    0.1996    0.4453]
A=[0.6399    0.8965]
 if size(A)>size(B)
     A=A(size(B,1),:)
     social=B-A
 else
        [jj,kk]=size(A)
        [jjj,kkk]=size(B)
        zz=zeros(jjj,kkk)
        zz(1:jj,1:kk)=A   
        social=B-zz
 end

when i run the code it executes.

But when i run the code by changing A to B and B to A i am getting error for the following code:

A=[ 0.7684    0.0120;
    0.5333    0.9666;
    0.0684    0.8322;
    0.1996    0.4453]
B=[0.6399    0.8965]
 if size(A)>size(B)
     A=A(size(B,1),:)
     social=B-A
 else
        [jj,kk]=size(A)
        [jjj,kkk]=size(B)
        zz=zeros(jjj,kkk)
        zz(1:jj,1:kk)=A   
        social=B-zz
 end

Could you please help me to solve the issue.I want to form the code in such a way the code needs to be executed when size(A) > size(B) and when size(B)> size(A)

[John D'Errico]

Your problem is that you do not understand how if statements work in MATLAB, or you do not understand what size returns.

B=[ 0.7684    0.0120;
    0.5333    0.9666;
    0.0684    0.8322;
    0.1996    0.4453]
A=[0.6399    0.8965]

Now, what are size(A) and size(B)?

size(A)
ans =
     1     2
     
size(B)
ans =
     4     2  

Now, what happens when you use if?

help if
 if Conditionally execute statements.
    The general form of the if statement is
 
       if expression
         statements
       ELSEIF expression
         statements
       ELSE
         statements
       END
 
    The statements are executed if the real part of the expression 
    has all non-zero elements.

So, what hapens when you try the statement:

 if size(A) > size(B)

What does that comparison return?

size(A) > size(B)
ans =
  1×2 logical array
   0   0

Does the REAL part of that result have ALL non-zero elements?

Instead, you might want to use the second argument to size. For example, do a comparison like this:

if size(B,1) > size(A,1)
    disp('IT WORKS!')
else
    disp('The sky is falling.')
end

IT WORKS!

So when B had more rows in it than A, the if branch executes. See what happens when we change the if clause to not use the second argument to size, even though we know that B indeed is a "larger" array than A, that is, it has more rows than A.

if size(B) > size(A)
    disp('IT WORKS!')
else
    disp('The sky is falling.')
end

The sky is falling.

So the primary branch in the if failed to execute, dropping down into the else clause.

The point is, you need to understand how the if statement works. You need to understand size.