Suppose you plot a line, as just two points, between (0,1) and (2,4).
h = plot([0 2],[1 4],'o-')
h =
Line with properties:
Color: [0 0 1]
LineStyle: '-'
LineWidth: 0.5
Marker: 'o'
MarkerSize: 6
MarkerFaceColor: 'none'
XData: [0 2]
YData: [1 4]
ZData: [1×0 double]
You can now extract the points that you plotted.
h.XData
ans =
0 2
h.YData
ans =
1 4
But MATLAB does not allow you to extract all the points in between along that line segment. Of course, there are infinitely many of them. But even if your goal is to obtain the pixelated points along that line, you still cannot do so. Sorry.
Nothing stops you from using interpolation to obtain a set of interpolated points. interp1 will help you there. But that is all you can do.
Finally, it looks like you are looking to compute an intersection of two curves in a plot.
The simp[lest way to do this, if you have actual functions, is to use a tool like fzero. Subtract the functions, then solve for a zero point.
If you want to do this form data points, then use a tool like Doug Schwarz's intersections.m, available from the file exchange.
If you want to do it from a plot itself, then you need to extract the points from the plot, then use intersections on the extracted curves.
