For loop changing variables and comparing results

time_range = 10;

y = zeros(1,time_range);

for t = 1:1:length(time_range)

x = 0.5;

y(t) = x .* t;

end

plot(time_range,y)

If I want to change x from 0.5 to 1 and compare the results on the same graph how would I do this? I do not want to simply copy and paste the for loop again and change the value of x. Is there a way to do this?

Answer 1

[Isiah Pham]

time_range = 10;

y = zeros(1,time_range);

for x = 0.5:0.5:1

for t = 1:1:length(time_range)

x = 0.5;

y(t) = x .* t;

end

hold on

plot(time_range,y)

end

Just do the same code but put it in a for loop where x goes from 0.5 to 1

[Justin Hayes]

Thank you. I think I understand what you mean, however, when I used this code it produces an empty plot. Any suggestions?

[Isiah Pham]

tme_range is a single number the length of time_range is one so t is only run once. When t is plotted against y, it plots pne thing all at 10,y. If you would want a line of 0.5x or 1x, plot basically puts a bunch of points from the first and second inputs and draws a line between each.

plot(a,b) would make a point at (a(1),b(1)), (a(2), b(2)), etc. and then draw a graph

If I was doing this problem, I would instead just have a set of x-values and y-values without the time_range:

%X-values
x = [1:10]

%Loop runs the same plot for y = 0.5x and y = 1x
for coeff = 1:2
    %Makes the same x-matrix for y but times 0.5 or 1
    y = 0.5*coeff.*x
    
    %Plots x against y
    hold on 
    plot(x,y)
end

If you want to keep the code similar to your original code, then you would have to adjust the second for loop and plot(time_range,y)

Answer 2

[Ameer Hamza]

In MATLAB, you can make the code simpler and easy to read by replacing for-loop with vectorized operations.

time_range = 1:10;
x = 0.5:0.1:1;
y = x(:).*time_range;
plot(time_range,y)