data extract from 3d line plot?

Answer 1

[Max Murphy]

See example code and modify according to your data:

%% Make test data
fig = figure;
ax = axes(fig);

nPoint = 1001;
nSeries = 5;
k = ones(nSeries,1) * linspace(0,100,nPoint);
theta = randn(nSeries,1);

% Toy x-data
x = cos(k.*2*pi*0.1+2*pi.*theta).^(randi(4,5,1)).*(randn(nSeries,1) * 10);

% Toy y-data
y = randn(nSeries,nPoint) .* (randn(nSeries,1) * 10);

% Toy z-data
z = sin(k.*2*pi*0.1 + 2*pi.*theta).*(randn(nSeries,1) * 10);

% Labels
lab = cell(nSeries,1);
for i = 1:nSeries
   lab{i} = sprintf('TestData %g',i);
end

% Plot them
plot3(ax,x.',y.',z.');
legend(lab);

%% Get 3D data
% Can use 'gca' here if don't have 'ax' handle
c = findobj(ax,'Type','line'); 
% c = findobj(gca,'Type','line'); % should work for your data

% This returns data in cell array, where each element matches
X = get(c,'XData'); % X{1,1} corresponds to Y{1,1} and Z{1,1}
Y = get(c,'YData'); % Y{2,1} corresponds to X{2,1} and Z{2,1} etc
Z = get(c,'ZData');

Answer 2

[Image Analyst]

If all you have is that one 2-D image, you can't. Exactly what data do you have? Are you the one who plotted it? If not, can you get it from them. Otherwise can you get the formulas that made those curves?