Issue with plotting order

Hello,

I have been trying to plot a shaded area (right y-axis) behind two lines (left y-axis), as shown in the code below. However, the shaded area always appears last, covering up the two lines. I've done this kind of graph before but have never had this issue. Best I can tell, it is because the right y-axis is plotted last. Is there a way to make the right y-axis plotted first? I can't simply switch which data is on the axis, unfortunately: they need to be in this order. Thanks for any help!

clear; clc; close all;
Data = xlsread("FigureOfMeritResults.xlsx");
% Extract data
Date = Data(469:1908,1);
FoM = Data(469:1908,3);
GHI = Data(469:1908,4);
% Calculate the running average over 5 data points
FoM_avg = movmean(FoM, 5);
GHI_avg = movmean(GHI, 5);
dFoM = zeros(length(FoM),1) + mean(FoM);
ticks = {'12:00AM','4:00AM','8:00AM','12:00PM','4:00PM','8:00PM','12:00AM'};
fz = 15;
%%
fig = figure;
set(gcf,'Color','w','Units','inches')
set(gcf,'Position',[1,1,5,6])
GHI_color = [0.8 0.8 1];
yyaxis left;
p1 = scatter(Date, FoM, 'Marker', '.', 'SizeData', 15, 'MarkerFaceColor', "#0072BD");
hold on;
p2 = scatter(Date, dFoM, 'Marker', '_', 'SizeData', 15, 'MarkerFaceColor', 'black');
hold on;
ax = gca;
ax.YColor = 'k';
yyaxis right;
xData = [Date; flipud(Date)];
yData = [zeros(size(GHI)); flipud(GHI)];
fillHandle = fill(xData, yData, GHI_color,'EdgeColor','none');
hold on;
ax = gca;
ax.YColor = 'k';
xlabel('Time of Day (hrs)', 'FontSize', fz);
numTicks = length(ticks);
tickPositions = linspace(min(Date), max(Date), numTicks);
xticks(tickPositions);
xticklabels(ticks);

set(gca, 'FontSize', fz);
ax = gca;
box on;
set(ax,'BoxStyle','full','LineWidth',2,'XGrid','off','XMinorTick','off','YGrid','off',...
    'YMinorTick','on');

Answer 1

[Jatin]

Hi @Emily Barber,

If you refer to the documentation on "Graphics Objects Hierarchy," you'll see that the plotting order is based on the sequence in which graphic objects are created. In your code, since the shaded area is plotted last, it should appear on top of the lines.

A solution to this should be using "uistack" function to bring the lines to the front. Apparently, If you go through the following MATLAB Answers post, people have noticed that using "uistack" does not seem to work with "yyaxis" and have adviced to use "SortMethod" property to fix this as a workaround.

https://www.mathworks.com/matlabcentral/answers/280015-draw-stack-order-for-yyaxis

https://www.mathworks.com/matlabcentral/answers/855500-uistack-giving-error-with-yyaxis

Please check if the following workaround is effective for you:

clear; clc; close all;
Data = xlsread("FigureOfMeritResults.xlsx");
% Extract data
Date = Data(469:1908,1);
FoM = Data(469:1908,3);
GHI = Data(469:1908,4);
% Calculate the running average over 5 data points
FoM_avg = movmean(FoM, 5);
GHI_avg = movmean(GHI, 5);
dFoM = zeros(length(FoM),1) + mean(FoM);
ticks = {'12:00AM','4:00AM','8:00AM','12:00PM','4:00PM','8:00PM','12:00AM'};
fz = 15;
%%
fig = figure;
set(gcf,'Color','w','Units','inches')
set(gcf,'Position',[1,1,5,6])
GHI_color = [0.8 0.8 1];
yyaxis left;
p1 = scatter(Date, FoM, 'Marker', '.', 'SizeData', 15, 'MarkerFaceColor', "#0072BD");
hold on;
p2 = scatter(Date, dFoM, 'Marker', '_', 'SizeData', 15, 'MarkerFaceColor', 'black');
hold on;
ax = gca;
ax.YColor = 'k';
yyaxis right;
xData = [Date; flipud(Date)];
yData = [zeros(size(GHI)); flipud(GHI)];
fillHandle = fill(xData, yData, GHI_color,'EdgeColor','none');
hold on;
ax = gca;
ax.YColor = 'k';
xlabel('Time of Day (hrs)', 'FontSize', fz);
numTicks = length(ticks);
tickPositions = linspace(min(Date), max(Date), numTicks);
xticks(tickPositions);
xticklabels(ticks);

set(gca, 'FontSize', fz);
set(gca, 'SortMethod', 'depth')
ax = gca;
box on;
set(ax,'BoxStyle','full','LineWidth',2,'XGrid','off','XMinorTick','off','YGrid','off',...
    'YMinorTick','on');

You can know more about 'SortMethod' by referring to the documentation below:

https://www.mathworks.com/help/releases/R2023a/matlab/ref/matlab.graphics.axis.axes-properties.html?searchHighlight=SortMethod&s_tid=doc_srchtitle#budumk7_sep_shared-SortMethod

Hope this helps!

[Emily]

Thank you for this quick response. Oddly, I have tried switching this before to no avail, and using the uistack function causes the following error:

Error using matlab.graphics.axis.Axes/set

Children may only be set to a permutation of itself.

Error in uistack (line 160)

set(UParent,'Children',AllChildren);

Error in Backgroundarea (line 43)

uistack(p1)

I have attached the input file to this comment. Please let me know if I can provide any more information.

[Emily]

Thanks. Yes, I noticed that the right y-axis is being plotted second. Unfortunately I am not able to switch the axis in this case. Thank you for trying to help, however.

[Jatin]

Hi @Emily Barber,

Please see if my revised answer helps resolve the issue for you.

[Emily]

This worked! Thank you so much!

[Jatin]

My pleasure!

Answer 2

[Voss]

Data = readmatrix("FigureOfMeritResults.xlsx");
% Extract data
Date = Data(469:1908,1);
FoM = Data(469:1908,3);
GHI = Data(469:1908,4);
% Calculate the running average over 5 data points
FoM_avg = movmean(FoM, 5);
GHI_avg = movmean(GHI, 5);
dFoM = zeros(length(FoM),1) + mean(FoM);
ticks = {'12:00AM','4:00AM','8:00AM','12:00PM','4:00PM','8:00PM','12:00AM'};
fz = 15;

%%
fig = figure;
set(gcf,'Color','w','Units','inches','Position',[1,1,5,6])
GHI_color = [0.8 0.8 1];

xData = [Date; flipud(Date)];
yData = [zeros(size(GHI)); flipud(GHI)];
fillHandle = fill(xData, yData, GHI_color,'EdgeColor','none');
ax1 = gca();
set(ax1, ...
    'Box','off', ...
    'FontSize',fz);
xlabel(ax1,'Time of Day (hrs)', 'FontSize', fz);
tickPositions = linspace(min(Date), max(Date), numel(ticks));
xticks(ax1,tickPositions);
xticklabels(ax1,ticks);
drawnow
ax1.PositionConstraint = 'innerposition';

ax2 = axes(fig, ...
    'Units',ax1.Units, ...
    'Position',ax1.Position, ...
    'Color','none', ...
    'FontSize',fz, ...
    'XAxisLocation','top', ...
    'YAxisLocation','right', ...
    'XTick',tickPositions, ...
    'XTickLabel',{}, ...
    'PositionConstraint','innerposition', ...
    'NextPlot','add');
p1 = scatter(ax2, Date, FoM, 'Marker', '.', 'SizeData', 15, 'MarkerFaceColor', "#0072BD");
p2 = scatter(ax2, Date, dFoM, 'Marker', '_', 'SizeData', 15, 'MarkerFaceColor', 'black');

set([ax1 ax2], ...
    'LineWidth',2, ...
    'XGrid','off', ...
    'XMinorTick','off', ...
    'YGrid','off',...
    'YMinorTick','on');

linkaxes([ax1 ax2],'x')