Calculate the sum of these two vectors using loops. Can't use sum()

Use loops to calculate the sum of two row vectors a & b, each of dimension 9. c(i)=a(i) + b(i) for i=1:9;
My current code looks like this:
clear;
a=zeros(1,9);
b=zeros(1,9);
c=zeros(1,9);
for i=1:9;
c(i)= a(i)+ b(i);
end;
disp(c);

Answers (4)

Your code is ok although you just could have set
c=a+b;
I wonder why you are supposed to use a loop.
Best wishes
Torsten.
My output is just not right though.
output:
0 0 0 0 0 0 0 0 0

5 Comments

Why do you think this is incorrect?
isn't it suppose to work something like this:
a + b = c
1 1 1 1 1 1 1 1 1 + 1 1 1 1 1 1 1 1 1 = 2 2 2 2 2 2 2 2 2
2 2 2 2 2 2 2 2 2 + 2 2 2 2 2 2 2 2 2 = 4 4 4 4 4 4 4 4 4
3 3 3 3 3 3 3 3 3 + 3 3 3 3 3 3 3 3 3 = 6 6 6 6 6 6 6 6 6
etc etc up to 9
and then add up all the c's?
Or is my understanding of vectors wrong?
It actually works like that, but in your original post you're basically doing 0+0=0...
a=ones(1,9);
b=ones(1,9)*3;
c=zeros(1,9);
c=a+b;
disp(a);
disp(b);
disp(c);
You have
a=[0 0 0 0 0 0 0 0 0]
b=[0 0 0 0 0 0 0 0 0]
What you do in the loop is to sum a and b componentwise, thus
c=[0+0 0+0 0+0 0+0 0+0 0+0 0+0 0+0 0+0]
and the result is
c=[0 0 0 0 0 0 0 0 0]
Best wishes
Torsten.

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Ok, but I'm trying to replace the values of zero with 1,2,3...9, so how do I replace the loop to sum numbers 1:9
Sorry if my question wasn't clear enough.

1 Comment

If you want to sum numbers 1,...,9:
summe=0;
for i=1:9
summe=summe+i;
end
disp(summe);
Best wishes
Torsten.

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I attached the question to make things more clear

1 Comment

If this is the question, your original code is correct.
Best wishes
Torsten.

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Asked:

on 9 Apr 2015

Commented:

on 9 Apr 2015

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