PDFPLOT displays a histogram of the empirical probability density function (PDF) for the data in the input array X using nbins number of bins.
If input X is a matrix, then pdfplot(X) parses it to the vector and displays PDF of all values.
For complex input X, pdfplot(X) displays PDF of abs(X).

Example:
y = randn( 1, 1e5 );
pdfplot( y );
pdfplot( y, 100 );

As somebody other already mentioned:
Be careful, to get the real PDF estimate replace
bar(X, N/sum(N));
with
bar(X, N/sum(N)/step);

23 Jun 2008

Paul Beekhuizen

Nothing more than just a standard histogram with cleverly chosen bins. Much better techniques exist to display a pdf. On top of that, it is buggy (although this can be easily fixed by the fix proposed in one of the other reviews).

20 Feb 2008

Jon Hyde

06 Feb 2008

Sean Winfree

Yes, the fix suggested by Tim Hattrell
returns the correct pdf. Thanks Tim

07 Jan 2008

seema sudevan

04 Jun 2007

Tim Hattrell

I don't think this calculates the correct PDF as the area under the graph is not one. Replace bar(X, N/sum(N)); with bar(X, N/sum(N)/step); to fix this.

01 May 2007

Eoin Elliffe

It would be nice if you could do Ntigram as for pdf you generally need variable bin sizes.

06 Mar 2007

Hong La

Okey, i seem it to be my need but not. This is not new thing, a little simple.

01 Dec 2006

Jonathan Duplicy

good job - what I need.
unbelievable it's not included in stat. toolbox

03 Aug 2006

Li jia

just what i want, thank you

19 Mar 2006

anonym anonym

check how it works:
plot(-3:0.1:3,pdf('norm',-3:0.1:3,0,1))
hold
pdfplot(x,30)

23 Dec 2005

Norbert Pierre

Allows visualization of the data. An extremely useful utility.