Get a point from a graph
显示 更早的评论
Hie guys, I have done a GUI to plot a graph. Now i would like to get the calue from the graph. Lets say i plot(x,y). I would like to get the value out, for example when x=4, what is the value of y. I know there is a datacursormode, but it only show me the value in the graph. In this case, i would like to get the value in the command window.
Thanks Ean
采纳的回答
Paulo Silva
2011-2-15
You can retrieve the plotted data, for example:
XData=get(get(gca,'children'),'XData');
YData=get(get(gca,'children'),'YData');
Now if you want to know the y value when x=4 just do
YData(XData==4)
6 个评论
Matt Fig
2011-2-15
Note that the final line may fail. If you get an empty value for that line, use the INTERP1 function instead.
y_4 = interp1(XData,YData,4);
Ean Soo
2011-2-16
Matt Fig
2011-2-16
For example:
x = -4:.1:4;
y = x.^2;
plot(x,y)
XData=get(get(gca,'children'),'XData');
YData=get(get(gca,'children'),'YData');
% Get y value for x=3.33 - NOT a data point.
y_3p33 = interp1(XData,YData,3.33,'spline')
Paulo Silva
2011-2-16
Children in that case refers to the Line made by the plot.
Ean Soo
2011-2-16
Nasiru Umar Bagudu
2022-2-5
What if i want to get the value of x when y is zero for example?
更多回答（1 个）
Walter Roberson
2011-2-15
0 个投票
You can use a custom datacursormode callback that includes display() in its code.
类别
在 帮助中心 和 File Exchange 中查找有关 2-D and 3-D Plots 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
