How to plot a large data set with markers to differentiate two overlapping lines?

Hi, Please I have large data sets to plot. The data sets is more than 100, 000 data points. I need to use markers or means of differentiating the lines when printed in balck and white. Reviewers of my work suggetsed that i should use marker. Each time i use marker I get a clumsy and messy plots as shwon below. Now I used colors to diffrentaite the two plots but printing in black and white does not reveal the distintion of the two plots. I have read what @image analyst explained in this https://www.mathworks.com/matlabcentral/answers/57241-plot-large-dataset-with-sample-points#answer_69235 but it is not working for me. I need to be able to differentiate the two plots. The code of my plot is below. The plots are also shown below.

How do i modify the code to get two distinct plots in balck and white?

the first plot is when i used marker. Please note that only one plot dominate due to large data points with marker.

the second plot is when i didnt use any marker but color distintion. However, it dissappears after printing in balck and white.

plot(t,n_d,'r-')

% plot(t,R_react)

% plot(t,T_l)

% plot(t,T_react)

hold on

plot(t,n_r, 'bo')

legend('Desired power','Actual power')

ylabel('Reactor core relative power')

% ylabel('Reactivity due to control rod during load droping')

% ylabel('Exit temperature of coolant during load dropping')

% ylabel('Total reacticity during load dropping')

% plot(t,U)

% ylabel('Control gain')

xlabel('Time (s)')

hold off

norm(Ustc);

Answer 1

[Alan Stevens]

How about plotting every n points. For example

plot(t(1:1000:end),n_d(1:1000:end),'o')
hold on
plot(t(500:1000:end),n_r(500:1000:end),'s')

Answer 2

[KaMATLAB]

Thank you very much for the adjustment and the insight. However, I want the plots to be distinct and the markers to be disticnt as well. They are crowded together. I tried to adjust the interval so that i can have the markers for the different plots at different intervals.

I got the plot below after the adjustment based on your opinion. It seems clumsy and crowded together.

Thank you

Moreover, I want the Linestyle of the two plots to be obvious and the colors to be more distinct. Thank you

[Alan Stevens]

Make the spacing larger! i.e. change the interval to 1500 or 2000, or whatever gives a clearer result.

[KaMATLAB]

Thank you very much. I have been able to combine your thoughts and MarkerIndices command. They are both giving desired results.