Drawing a 1-CDF Graph

Hi everyone, I want to ask how do I draw a 1-cdf graph on matlab?

I have a set of data and I have already plotted a regular cdf using ecdf(data set). However, when I simply put 1-ecdf(data set), matlab returns me a vector. I have also tried plot(X,1-ecdf(data set)) but it looks completely wrong. X is just a vector I used for my data points. Can anyone help me out?

F=SGLD_cdf(X,Sigma,r,deta,b)

Y1 = n(1:1529:end,:);

figure(2)

plot(X,F)

hold on

% SGLD_cdf is a function created in another script, while X = 0.1:0.1:max(n) where n is my dataset

ecdf(n)

hold on

legend('Fitted curve','Data Set')

[KSSV]

What are dimensions of n? You are getting any error?

[See Kai Xiang]

n is a 261345x1 vector. The above code is able to generate out 2 CDF curves nicely with no issues. However, what I require is a 1-cdf curve, which is essentially a flipped CDF curve.

Answer 1

[Neelanshu]

Hi See Kai Xiang,

I understand that you are looking for a way to plot 1-CDF of the data.

To plot the 1-CDF, you can utilize the function values and x intervals obtained from MATLAB's "ecdf" function. The following MATLAB script demonstrates how to do this:

% Generate some example data, e.g., random numbers from a normal distribution
data = randn(1000, 1);

% Calculate the CDF values and the corresponding x values (sorted data)
[f, x_values] = ecdf(data);

% Calculate the 1-CDF
one_minus_f = 1 - f;

% Plot the 1-CDF and CDF
figure;
ecdf(data) % plots CDF
hold on;
plot(x_values, one_minus_f);
xlabel('Data values');
ylabel('1-CDF/ CDF');
title('CDF plots of the data');
legend('CDF Data', '1-CDF Data')
grid on;

You may refer to the following documentation to learn more about "ecdf" function :

https://in.mathworks.com/help/stats/ecdf.html

Hope this helps.