I understand that you want to edit the contents of a variable x by dragging its plotted points so that the corresponding entries in x update automatically.
The issue with using a simple plot(x,'*') is that it only draws markers, which are not draggable by default.
The main change I made was to replace the static plot markers with “drawpoint” objects. Each data point is created as a draggable ROI, and I added listeners that trigger whenever a point is moved. Inside the callback, the x-coordinate is locked so that the index of the data point cannot change, only its y-value. The callback then updates the corresponding element of x and refreshes the line plot so that the results are immediately visible.
Here is my implementation for the same:
function drag_points
% Initial data
x = rand(5,1);
% Figure and axes
f = figure('Color','w');
ax = axes('Parent',f); hold(ax,'on'); box(ax,'on');
xlim(ax,[0.5 5.5]);
xlabel(ax,'Index'); ylabel(ax,'Value');
% Line plot for context
hLine = plot(ax, 1:numel(x), x, 'b-*', 'MarkerSize',8, 'LineWidth',1.2);
% Make draggable points
for k = 1:numel(x)
p = drawpoint(ax,'Position',[k x(k)],'Deletable',false);
addlistener(p,'MovingROI',@(src,evt) onMove(src,k));
addlistener(p,'ROIMoved', @(src,evt) onMove(src,k));
end
% Callback to update variable
function onMove(src,idx)
pos = src.Position;
pos(1) = idx; % lock to index
src.Position = pos;
x(idx) = pos(2); % update variable
hLine.YData = x; % refresh line
end
end
<I have attached a video depicting the desired funcitonality.>
You can refer the documentation links below for more details:
