Easy Answer: If you are using R2016a or newer, use yyaxis instead of plotyy. yyaxis lets you use any plotting command, e.g.
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.
- Learn more here: Using Graphics Objects