How to mark a specific point on CDF graph?

Hi,

I have some query.

1. How can I mark a specific point on my CDF curve. For example, If I want to describe my proposed scheme and Comparison scheme performance on 80%, how I plot that error values in x-axis? If I plot them, the figure is becoming more conjusted. How can I present this figure?
2. I want to draw a vertical dotted line for 80% of each CDF on the x-axis. How can I do that?
3. How can I make the CDF curve smoother?
4. Is there any effcient way to describe the CDF curve? How can I describe this graph?

Thank you for your kind help and time.

Answer 1

[Ridwan Alam]

Assuming you have 4 cdf arrays, you can find the x-values as:

cdf1ind = find(cdf1>=.80,1,'first'); x1 = x(cdf1ind);
cdf2ind = find(cdf2>=.80,1,'first'); x2 = x(cdf2ind);
cdf3ind = find(cdf3>=.80,1,'first'); x3 = x(cdf3ind);
cdf4ind = find(cdf4>=.80,1,'first'); x4 = x(cdf4ind);

I would just plot the points instead of the line. For your existing figure:

hold on; plot(x1,cdf1(cdf1ind),'o');  % similarly for cdf2, cdf3, cdf4

To plot a dotted line on those x values:

hold on; line([x1,x1],[0,cdf1(cdf1ind)],'LineStyle','--');

To make the cdf curve smoother, try interp1() or something similar.

newcdf1 = interp1(x,cdf1,linspace(min(x),max(x),10*numel(x)));

The last question: that's totally upto you, what aspect of the idea you want to highlight.

[Tania Islam]

[Tania Islam]

Thank you so much.

[Ridwan Alam]

Sure. Glad to help.