Is it possible to save plotted points?

The general idea is that I am plotting a parabola and using 'r.' to plot it in red dots.

Is there a way I can save these dot/points? I need the location, and I am randomly generating the parabola so this would definitely be ideal.

If not, could I have a suggestion to best do what I am hoping to acheive? I am sure more info is needed, so please ask away and I can clarify.

Answer 1

[Rik]

Either save the data you use to create the plot, or retrieve that data from the XData and YData properties of the line object created by plot.

[Kayleigh Movalli]

Can I still do that if I am just calculating it via an equation?

Without iterations, I struggle to see how I can save the data.

How would I save the XData and YData?

Thank you for taking the time to respond.

[Rik]

What code are you using to create the plot?

[Kayleigh Movalli]

This is the code:

I am using random numbers ( num = randi(1000) ) in place of the numbers provided. This is from another forum post.

   x=-10:0.1:10;
   y=sqrt((36-x.^2)/9);
   plot(x,y)

[Rik]

So why can't you save x and y directly? Anyway, the code below shows what I mean.

h=plot(x,y);
x=h.XData;y=h.YData;

[Adam Danz]

save('myData.mat','x','y')

[Kayleigh Movalli]

Thanks a lot, guys.

It appears to have the x and y saved like this:

0.000000000000000e+00 + 2.906790642616011e+02i

Is it possible to receive an integer or does this have to do with how I am generating and plotting the numbers?

[Adam Danz]

That appears to be a complex number (ie, sqrt(-1)).

If you weren't expecting imaginary components, that's usually a sign that something in your analysis isn't working the way it's intended. You could extract the real part using real(x) which is 0 but I doubt that would address the real problem, unless you're expecting a complex number.