Problem in finding PDF of a set of samples
1 Ansicht (letzte 30 Tage)
Ältere Kommentare anzeigen
I want to get PDF of a set of samples, A, from its histogram:
[n,x] =hist(A,Number_bins);
when I use the following code:
pdf=n/sum(n(:));
with different number of bins I get different results, to fix it I use this code
pdf=n/sum(n(:))/diff(x(1:2));
but some of numbers in pdf would be greater than one! (the probability should not be greater than one)
I really don't understand where the problem is. I would appreciate if you you could help me. Thank you.
0 Kommentare
Antworten (1)
Image Analyst
am 30 Sep. 2013
Of course the PDF is different if you have different bin sizes. But most important is how you plan on using the PDF. What do you plan on doing with it? I think n/sum(n) is fine - you just have to know what you're dealing with when it comes time to use it. It tells you the probability of a sample falling into that bin.
3 Kommentare
Image Analyst
am 1 Okt. 2013
Don't divide by the diff. And of course the PDF will vary according to the number of bins. Computers are digital - you can't have an infinite number of bins. It can't be continuous. It must be quantized and since the number of counts in the quantized pdf must equal the number of elements in your array, the value per bin must be different. My other question, about what you plan on doing with it, remains unanswered.
Siehe auch
Produkte
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!