How to plot graph using ginput?
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Hi friends i want to plot a graph between two graphic input, i did it but i want to make it as my input should be visible before plotting.
This is my code..
axis([0 100 0 100]);
hold on
nodes = 2;
PauseTime = 0.05;
[x,y] = ginput(nodes);
plot(x,y,'--ys','LineWidth',2,'MarkerEdgeColor','b','MarkerFaceColor','b', 'MarkerSize',4);
please help me....
采纳的回答
OCDER
2017-10-30
To do what you want would require using callback functions. See this video here to understand how it works: https://blogs.mathworks.com/videos/2008/05/27/advanced-matlab-capture-mouse-movement/
To summon this function, do:
plotLines(5) %for 5 points, 4 lines
The function is below. You have to modify this based on what you want to accomplish with drawing lines. Play around with the callback functions: startLine, stopLine, dragLine.
function plotLines(nodes)
axis([0 100 0 100]);
set(gca, 'xlim', [0 100], 'ylim', [0 100]);
hold on;
%nodes = 2; %It's now the function input
PauseTime = 0.05; %You can use drawnow instead of pause to refresh plots.
set(gcf, 'WindowButtonDownFcn', @startLine);
set(gcf, 'WindowButtonUpFcn', @stopLine);
function startLine(varargin)
pt = get(gca, 'currentpoint');
if isempty(findobj(gca, 'type', 'line'))
plot(gca, [pt(1,1), pt(1,1)], [pt(1,2), pt(1,2)], '--ys', 'LineWidth',2, 'MarkerEdgeColor','b', 'MarkerFaceColor','b', 'MarkerSize',4);
else
Lx = findobj(gca, 'type', 'line');
Xdata = get(Lx, 'Xdata');
Ydata = get(Lx, 'Ydata');
if length(Xdata) > nodes-1; return; end %Edit this depending on your definition of "node".
Xdata(end+1) = pt(1,1);
Ydata(end+1) = pt(1,2);
set(Lx, 'Xdata', Xdata, 'Ydata', Ydata);
end
set(gcf, 'WindowButtonMotion', @dragLine)
end
function dragLine(varargin)
pt = get(gca, 'currentpoint');
Lx = findobj(gca, 'type', 'line');
Xdata = get(Lx, 'Xdata');
Ydata = get(Lx, 'Ydata');
Xdata(end) = pt(1,1);
Ydata(end) = pt(1,2);
set(Lx, 'Xdata', Xdata, 'Ydata', Ydata);
end
function stopLine(varargin)
set(gcf, 'WindowButtonMotion', '');
end
end
5 个评论
VALARMATHY K
2017-10-31
sorry i don't want to do this with call back, i just what i want is, if select two points in my graph, after plot i am getting a stright line between that two points (two blue dots), i want that when i click cursor one blue dot shoud be shown on my graph..
This is my output when i click 1st point
This is output after 2nd click because i assigned only 2 nodes..
OCDER
2017-10-31
Have you tried the callback solution? The other way to do this is to use multiple ginputs. 1st ginput - draw the 1st point only. 2nd ginput - draw the 2nd point and the line.
axis([0 100 0 100]);
hold on
nodes = 2;
PauseTime = 0.05;
[x,y] = ginput(1);
Lx = plot(x,y,'--ys','LineWidth',2,'MarkerEdgeColor','b','MarkerFaceColor','b', 'MarkerSize',4);
for k = 1:nodes-1
[x,y] = ginput(1);
Lx.XData = [x, Lx.XData];
Lx.YData = [y, Lx.YData];
end
VALARMATHY K
2017-10-31
when i run this code i am getting this error....
OCDER
2017-10-31
Hm, that's odd. Do you have an older version of Matlab? Try this instead:
clear
close all
clc
axis([0 100 0 100]);
hold on
nodes = 2;
PauseTime = 0.05;
[x,y] = ginput(1);
Lx = plot(x,y,'--ys','LineWidth',2,'MarkerEdgeColor','b','MarkerFaceColor','b', 'MarkerSize',4);
for k = 1:nodes-1
[x,y] = ginput(1);
XData = get(Lx, 'XData');
YData = get(Lx, 'YData');
set(Lx, 'Xdata', [x, XData], 'YData', [y, YData]);
end
VALARMATHY K
2017-11-1
更多回答（1 个）
Walter Roberson
2017-10-31
0 个投票
3 个评论
VALARMATHY K
2017-11-1
Walter Roberson
2017-11-1
Instead of using ginput() to get the coordinates, you could imline(), which allows the user to place a draggable resizable line -- so they could effectively select points and move the selection around and see the change in the line, without you having to program in the behaviours yourself.
VALARMATHY K
2017-11-6
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