MATLAB: How to extract detail data from matlab Plot

data importextractingplot

I have a plot in which there are 118 (x, y) points. Where x is not continuous. But plot has upto 490 datas when plotted. So how to extract all 490 data from the plot. Because if we use dataObjs we get only 118 points again.

Best Answer

If you plot only 118 points you can't get more from the plot. The results are interpolated and probably what you want is a continuous formula to model y as a function of x. If you have a polynomial data, take a look at the polyfit function from matlab. In case you really only want to have more refined values, you just need to interpolate the inbetween results yourself:

x = 1:118;
y = x.^2;
xq = linspace(x(1),x(end),490); % Here is the new points you want to generate
yq = interp1(x,y,xq,'pchip'); % Here is the actually interpolation
figure,plot(x,y,'*'),hold on,plot(xq,yq)