How to show 'Marker symbol' for specific values on 2D-plot?

In a plot of x (array with 6000 values) and f(x) (also array with 6000 values) I want to show 'Marker symbol' for specific values on 2D-plot? for example, show Marker symbol for f(x) at x(1000) or 2000,3000,4000,...on f(x) plot.

Answer 1

[Walter Roberson]

With newer MATLAB you can use the MarkerIndices property; see https://www.mathworks.com/help/matlab/creating_plots/create-line-plot-with-markers.html#bvcbmlx-1

Answer 2

[KSSV]

x = linspace(0,2*pi,6000) ;
y = sin(x) ;

figure
hold on
plot(x,y)
idx = 1:1000:length(x) ;
plot(x(idx),y(idx),'s','markersize',10)