MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

Learn moreOpportunities for recent engineering grads.

Apply Today
Asked by I Made on 11 Mar 2013

I have a3, it's data < 64x490 int16 > , and i wanted to do *row1*row1*1 then row2*row2*2 to row49*row49*49 and have the sum of it. And apply it to all other columns too. i have tried using this code :

[g,h]=size(a3); m=1:g; t=sum(a3(m,:).*a3(m,:).*m);

but i get this error message : ??? Error using ==> times Integers can only be combined with integers of the same class, or scalar doubles.

this code work only if we remove the .*m and become like this:

[g,h]=size(a3); m=1:g; t=sum(a3(m,:).*a3(m,:));

but the formula from **row1*row1*1** become **row1*row1** only, can anyone correct my mistake ?

*No products are associated with this question.*

Answer by Image Analyst on 11 Mar 2013

Try

m = int16(1:g);

Be aware that if the numbers get larger than 32767, they will clip.

Answer by Wayne King on 11 Mar 2013

The error you get is because

m = 1:g;

gives you a double precision vector, while a3 is int16. You can remove that error by casting m to int16

m = int16(1:g);

or a3 to double precision

a3 = double(a3);

but then you're going to get dimension error. Did you mean to have a for loop?

I Made on 11 Mar 2013

yeah you right, actually i need to be n=1,2,3,4,5... as i wanted to have a sum of(sampel(n)*sample(n)*n), where n is the number of row. to be more clear let me explain a bit :

so i have e.g

4 5 3

5 4 1

2 1 2

i wanted to got

78 60 23

and the process is like :

Column 1->(4*4*1)+(5*5*2)+(2*2*3) then Column 2->(5*5*1)+(4*4*2)+(1*1*3) then Column 3->(3*3*1+1*1*2+2*2*3)

How can i achieve this?

## 0 Comments