access to a element of a matrix

Basically I need to create a matrix of current values and access each element and call the same value in an equation.

I=[-40 -30 -20 -10 0 10 20 30 40];
w=0.035;
h=1.57;
% T=215.3*I^2*w^-1.5*h^-1   This the equation where I need to acces the I value each time from

[Sachin Shridhar Bhat]

So how do I access it?

Answer 1

[Priysha Aggarwal]

If you want to multiply each element of I matrix with some constant, you can directly do:

a = [ 1 2 3 4]
b = 2*a 
% b = [2 4 6 8] 

If you want to access each element in particular :

I=[-40 -30 -20 -10 0 10 20 30 40];
w=0.035;
h=1.57;

%iterate over I :
for c = 1:size(I)
    a = I(c) %this will give you one element of I at a time
    % now use T=215.3*c^2*w^-1.5*h^-1
end

Answer 2

[pankhuri kasliwal]

You can access elements of an array using

A = [1 2 3 4 5];
A(1);

if you have a matrix then you can access the elements using

a = [1 2 3;4 5 6;7 8 9]
a(2,3);

a(2,3) provides with the element 6 in 2nd row, 3rd column

T=215.3*I^2*w^-1.5*h^-1

instead of this you can do

T = 215.3 * (I .* I) * w^-1.5 *h^-1 ;

[Sachin Shridhar Bhat]

But I guess in this Iteration of 'I' dosen't happen