How to plot quadratic function using for loop in MATLAB?

How to plot quadratic function with different number of points in MATLAB?

Plot quadratic function $x^2$ in MATLAB

This is a very basic task to plot quadratic function $x^2$ in MATLAB. But there are some additional things that need to understand. First of all, one function was created for different values of $x$ that shows the behaviour of the graph and smoothness by increasing points.

Few other operations:

1. Plot same function in MATLAB using for loop
2. Display legend for each graph in for loop separately
3. Saving Images as PNG in folder

Built-in commands Used:

1. num2str -- used to convert numeric value to structure
2. sprintf -- used to formatted data as a string, which the user can store or further manipulate or display as appropriate.
3. saveas -- used to save the graphs generated in folder

n = [2 5 10 100 1e3];
for i = 1:numel(n)
    x = -n(i):n(i);
    y = x.^2;
    txt = ['number of points = ',num2str(2*n(i)+1)];
    plot(x,y,'b-*','DisplayName',txt)
    grid on;
    legend show
    saveas(gcf,sprintf('x^2_%d.png',n(i)));
end
  

OUTPUT