How to multiply each element separately from row first to next row in matrix?

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Hello,
I want to multiply elements in the first row to the next row within the matrix to get a vector ( without Prod() function , only use of loop)
Example,
% code
matrix [1,2,3;
4,5,6;
7,8,9]
v=[(1*4*7),(2*5*8),(3*6*9)]
I have an error code
% code
a=input('Enter a matrix');
z=[]
[m,n]=size(a);
for i=1:m
c=a(i,:)
c2=a(i+1,:)
d=c.*c2
z=[z,d]
end
Thanks in advance :)

Answers (2)

KSSV
KSSV on 30 May 2018
Edited: KSSV on 30 May 2018
a=input('Enter a matrix');
[m,n]=size(a);
iwant = zeros(1,n) ;
for j=1:n
P = 1 ;
for i = 1:m
P = a(i,j)*P ;
end
iwant(j) = P ;
end

Stephen23
Stephen23 on 30 May 2018
Edited: Stephen23 on 30 May 2018
Simpler:
M = [1,2,3;4,5,6;7,8,9];
P = 1;
for k = 1:size(M,1)
P = P .* M(k,:);
end
Giving:
>> P
P = 28 80 162
and just for comparison:
>> prod(M,1)
ans = 28 80 162

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