Pulling data from a Matlab plot

gcfdata.m

h = findobj(gca,'Type','Line');
xd = get(h,'XData');
yd = get(h,'YData');
if iscell(xd) && iscell(yd) % Multi plot object
	exprt = NaN*ones(length(yd{1}),length(yd)+1);
	exprt(:,1) = xd{1};
	for i = 1:length(yd)
		exprt(:,i+1) = yd{i};
	end
else % Single plot object
	exprt = NaN*ones(length(yd),2);
	exprt(:,1) = xd;
	exprt(:,2) = yd;
end
dlmwrite('~/figdata.txt',exprt,'precision',6)

Primitive data extraction routine for retrieving a comma delimited .txt file of a MATLAB

Useful for pulling data from MATLAB for PGFplot or other LaTeX rendering packages
Works with plot(), semilogx(), semilogy() and other Cartesian format figures on at least R2015a, 2015b, 2016a

Usage

• Run as a script or paste into the MATLAB console with the desired figure to extract as the current active figure (typically the last to be created).

Interpreting the output

• The first column will be the x axis labels i.e. from plot(*x*,y)
• The next columns will be the y axis data in the reverse order of the plot fn calls

Example:

figure();
plot(x,y1);
plot(x,y2);
plot(x,y3);

will be formatted as:

x, y3,y2,y1