Why does my code does not work in the if loop

Hi there,

The question ask us to filter out the temperatures that is less than 5 deg C. the output for my T variable is 1 by 539 double matrix. By applying if loop, how do i make temperature that is less than 5 deg C to be 0? The following is my codes:

beta=15; T0=56.2; %intial temperature

t=1:0.0167:10;

T=T0-beta*t;

for n=1:length(T)

    if T(n)<5

        T=0
    end

end

there is an error: Index exceeds matrix dimensions. Please help

[Jan]

There are no "if-loops". Only for and while create loops.

Answer 1

[ES]

Once you set T = 0 inside your if, you lose all the array you created by doing T=T0-beta*t;

so you should have done

      if T(n)<5
          T(n)=0
      end

instead of if, you can also do a

T(T<5) = 0

what this does is, for all values of T<5, it sets it to 0.