Adding 2 different length array

I have problem in adding 2 different length array e.g x=[1 2 3 4 5 6 ]', Y =[ 3 5 7 8 ]' Ans= 4 7 10 13 6 but I do not know how to get this answer ? in my code I have tried

dir_list=dir('v1_ch.txt');

vec1=[];

for j=1:12

data=dlmread(dir_list((j-1)*13+k).name,';',3 );

            latitude=data(:,1);
            longitude=data(:,2);
            ch4=data(:,3);

            vec1=vec1+ch4; % here I tried to add array together

end

but it does not work ?

[Jan]

Please edit your question and use the standard code formatting as explained in the "Markup help" link.

Answer 1

[the cyclist]

Arrays have to be the same size (or one has to be a scalar) to add them, otherwise it is ambiguous to MATLAB what should be done with the "leftover" elements.

In your case, you want to pad a zero onto the end of Y, so the addition could be done like this:

x = [1 2 3 4 5 6]';
y = [3 5 7 8]';

A = x + [y;zeros(2,1)];

This will result in A = [4 7 10 12 5 6]'. (This is not exactly what you wrote as your answer, but I am guessing it is what you meant.)

If you don't know ahead of time how many zeros you need to pad at the end, then you can use the size() or length() command to determine the array dimensions, to calculate how many zeros you need.

Finally, you might want to read the "Getting Started" guide. The basics of vector manipulation are covered there.

[Uday]

Sorry for mistake in typing

Answer 2

[Azmat Ameen]

function[t,x]=padding(t1,t2,x1,x2)
t=min(min(t1),min(t2)):max(max(t1),max(t2));
y1=zeros(1,length(t));
y2=y1;
y1((t>=min(t1))&(t<=max(t1)))=x1; 
y2((t>=min(t2))&(t<=max(t2)))=x2;
x=(y1+y2)
stem(t,x)
end                    

Use this function to pad zeros and you will get the addition of two different array with different length.