MATLAB: Is the line not showing up on the plot

forfor loopgraphgraphicgraphicslinelinesplot

I'm trying to plot a line by using a for loop to fill one array but it's not working. Here's an example of what doesn't work:
    close all
    figure
    hold on
    %this doesn't work
    y= zeros(1, 10);
    i=1;
    for x= 0:.1:10
        y(i)= sin(x);
        i=i+1;
    end
    plot(x, y)
    %this works though
    x= 0:.1:10;
    y= cos(x);
    plot(x, y)
    hold off
What am I doing wrong with the for loop?

Best Answer

The loop does not work because x is not a vector after the loop. You have used x as the index variable, which is a scalar. Change your loop to this:
x = 0:.1:10;
y = zeros(size(x));
for i=1:numel(x)
    y(i)= sin(x(i));
end
Now x is still a vector after the loop.
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