How to insert a line over a heatmap using code?

38 views (last 30 days)
How can I insert a line over a heatmap in my code? I would rather not use the figure tools manually because I have to do multiple lines.

Answers (3)

Robert U
Robert U on 15 Jun 2018
Hi Samantha Clayton:
Since I do not know your code I can only demonstrate in the following example how to draw a vertical and a horizontal line into a contourf-plot (assuming you mean something like that).
Z = peaks(20);
ah = axes;
h = contourf(Z,10,'Parent',ah);
hold(ah,'on')
plot(ah,[0 25],[10 10],'white') % horizontal line
plot(ah,[10 10],[0 25],'white') % vertical line
ah.XLim = [2 20];
ah.YLim = [2 20];
There is a HeatMap-Command in Bioinformatics toolbox, so I do not know whether same strategy is working for that.
Kind regards,
Robert

Robert U
Robert U on 5 Sep 2022
Since the thread has be re-activated:
Here, a solution for heatmap tested in Matlab 2021b.
T = readtable('outages.csv');
h = heatmap(T,'Region','Cause');
% sloppy red line
annotation("line",[0.2 0.8],[0.2 0.8],"Color","red",'LineWidth',2)
% 2nd row horizontal line
plotLineThroughRowNr = 2;
nRow = numel(h.YData);
rowWidth = (h.InnerPosition(4))/(nRow);
lineYCoord = (nRow-plotLineThroughRowNr+0.5)*rowWidth + h.InnerPosition(2);
annotation("line",[h.InnerPosition(1) h.InnerPosition(1)+h.InnerPosition(3)],[lineYCoord lineYCoord],"Color","yellow",'LineWidth',2)
% 3rd column vertical line
plotLineThroughColumnNr = 3;
nColumn = numel(h.XData);
columnWidth = (h.InnerPosition(3))/(nColumn);
lineXCoord = (nColumn-plotLineThroughColumnNr+0.5)*columnWidth + h.InnerPosition(1);
annotation("line",[lineXCoord lineXCoord],[h.InnerPosition(2) h.InnerPosition(2)+h.InnerPosition(4)],"Color","magenta",'LineWidth',2)

Ahmed
Ahmed on 27 Aug 2024
Use MATLAB's imagesc instead of heatmap

Categories

Find more on Data Distribution Plots in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!