how to extract error data from a error plot

I have an error plot, and I want to extract the data (x,y, and error values) from this. How do I do this?

Thanks

[Walter Roberson]

Do you mean a plot created with errorbar() ?

[CLARK KENDRICK GO]

Yes, that's right. A plot that has been created with errorbar

[Walter Roberson]

Does it have error bars on the X Data, or only on the Y Data?

[CLARK KENDRICK GO]

delta along y data

Answer 1

[Walter Roberson]

The below assumes that the handle of the axes containing the errorbar() is in the variable ax such as ax = gca;

h = findobj(ax, 'type', 'errorbar');
if isempty(h)
    error('no errorbar found in axes designated by "ax"');
end
if numel(h) > 1
    warning('more than one errorbar found; outputs will be cell array')
end
X = get(h, 'XData');
Y = get(h, 'YData');
YNeg = get(h, 'YNegativeDelta');
YPos = get(h, 'YPositiveDelta');

If you had called errorbar using the form

errorbar(vector_of_x, vector_of_y, vector_of_error_values)

then YNeg and YPos will have the same content, and that content will be the same as the vector of error values.

If you had called errorbar using the form

errorbar(vector_of_x, vector_of_y, first_vector_of_error_values, second_vector_of_error_values)

then YNeg will have the same content as first_vector_of_error_values, and YPos will have the same content as second_vector_of_error_values.