You can change the marker size for a line plot by setting the “MarkerSize” property, either as a name-value pair or by accessing the “Line” object.
If you set this property as a name-value pair with the “plot” function, you must set it after all the x,y pairs. Name-value pair settings apply to all the plotted lines. To use a different marker size for each line, use separate “plot” commands. For example:
Accessing the “Line” object:
Alternatively, return the “Line” objects as an output argument from the “plot” function and then set the “MarkerSize” property for each object separately.
p = plot(x,x^2,'-k*', x,x^3,'-ko', x,x^4,'-k' )
p(1).MarkerSize = 20;
p(2).MarkerSize = 12;