Clear Filters
Clear Filters

Log-log plot which doen't display every values

5 views (last 30 days)
Flo
Flo on 1 Jul 2016
Commented: the cyclist on 4 Jul 2016
Hi everyone,
I believe some data I am playing with could be better displayed using a loglog plot. my vector:
y =
45 67
4 8
3 3
0 0
0 3
0 0
0 0
0 0
0 0
1 0
So, if I correctly plot that I should end-up with five marks on my graph right ? which is confirmed by the bar graph I get through my code:
So far my code only display three points... and I obviously need to display them all. Would you help me on that? Is it because the loglog function can't allow you don't display values equal to zero ?
my code:
none = length(one)
ntwo = length(two)
h(1:none,1)=one
h(1:ntwo,2)=two
[y,x]=hist(h)
stringTitle1 = 'test'
stringTitle2= ' comparison'
bar(x,y, 'group')
title('test title')
xlabel('test name') % x-axis label
ylabel('Frequency') % y-axis label
legend('XZ','YZ')
xLog = y(:,1)
yLog = y(:,2)
loglog(xLog,yLog,'.')
Cheers, Flo

Answers (1)

the cyclist
the cyclist on 1 Jul 2016
Edited: the cyclist on 1 Jul 2016
The basic problem is that log(0) is "equal" to negative infinity, so cannot be displayed.
  2 Comments
Flo
Flo on 4 Jul 2016
Edited: Flo on 4 Jul 2016
Alright, I see. it makes more sense. Would you suggest a way of better displaying a result like that :
Thank you for your help.
Flo
the cyclist
the cyclist on 4 Jul 2016
A simple option is to use a log(x+1) rather than a log(x) transformation to display the data. In other words, just add 1 to your data before using loglog. There are pros and cons to this approach. Here is one place you could read a bit about the practical aspects.

Sign in to comment.

Categories

Find more on Graphics Object Identification in Help Center and File Exchange

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!