# How do I add markers when using plotyy?

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Maurice on 14 Mar 2017
Commented: Ali on 29 Oct 2017
I'm plotting two curves using 2 different y-axes using plotyy. I would like to add markers to the data, and I can't figure out how to do that. The 'LineStyle' property will allow me to change from solid to dashed, etc; but won't let me change anything else.

Michelle Hirsch on 14 Mar 2017
Easy Answer: If you are using R2016a or newer, use yyaxis instead of plotyy. yyaxis lets you use any plotting command, e.g.
yyaxis left
plot(x,y,'-*') % Plot into left axes
yyaxis right
plot(x,z,'-o') % Plot into right axes
If you are on an older release, there's an example in the doc for plotyy called changing linestyles that gets you close. The difference is that instead of setting values for the LineStyle property, you set values for the Marker property
x = 0:0.01:20;
y1 = 200*exp(-0.05*x).*sin(x);
y2 = 0.8*exp(-0.5*x).*sin(10*x);
[hAx,hLine1,hLine2] = plotyy(x,y1,x,y2);
hLine1.Marker = 'o';
hLine2.Marker = '*';
If you aren't familiar with graphics objects like hLine1, a few tips:
• Display it at the command line to see some of the common properties you can control
• In the command window, hit the TAB key after typing "hLine1." to see a list of all properties.
Maurice on 17 Mar 2017
Thank You Michelle! Your last suggestion did the trick!
Ali on 29 Oct 2017
if true
--------------------------------------------------- code start
This is an example for your case
Input is "Input_Data", two dimension matrix
Marker_Counter=1;
figure6=figure;
Markers = {'+','o','*','x','v','d','^','s','>','<'};
for i=1:10:size(Input_Data,1)
TPR=Input_Data(i:i+9,7);
FPR=Input_Data(i:i+9,8);
plot(FPR,TPR,strcat('-',Markers{Marker_Counter}));
Marker_Counter=Marker_Counter+1;
hold on
end
plot([0.5 1],[0.5 1],'--');
legend('Minpts = 100','Minpts = 200','Minpts = 300','Minpts = 400','Minpts = 500','Minpts = 600','Minpts = 700','Minpts = 800','Minpts = 900','Minpts = 1000','','Location','SouthEast');
xlabel('FPR or (1-Specificity)','FontSize',12,'FontWeight','bold'); ylabel('TPR or Spensitivity)','FontSize',12,'FontWeight','bold');
title('ROC Space');
close(gcf);
-------------------------------------------- code end
end