# What is the proper way to set y tick labels for a histogram ?

Hi all,

I’m plotting the histogram of a data set:

x = datalist
bins= 100
hist(x,bins,normed=0) #returns a tupple (n,bins,patches)

Rather trivial… but instead of the plotting the counts n, I’d like to plot the realtive percentage counts, i.e. n/len(x). I can’t really use the option normed = 1 which plots n/(len(x)*dbins). I guess the simplest way would be to simply change the yticklabels (by dividing them by len(x)). The thing is that I simply cannot find out how to do this…

I tried using the axes.set_yticklabels() but doesn’t work. I’ve also tried to find the child containing the label but couldn’t find it (not in Axes, nor in YAxis etc…). I guess it must be a Text instance.

Can anyone give me a
hint,

Cheers,

Aure

···

Ne gardez plus qu’une seule adresse mail ! Copiez vos mails vers Yahoo! Mail

Hi Aure,

You could try:

ax.set_yticklabels(ax.get_yticks()/len(x))

/Antonio

Aur� Gourrier wrote:

···

Hi all,

I'm plotting the histogram of a data set:

x = datalist
bins= 100
hist(x,bins,normed=0) #returns a tupple (n,bins,patches)

Rather trivial... but instead of the plotting the counts n, I'd like to plot the realtive percentage counts, i.e. n/len(x). I can't really use the option normed = 1 which plots n/(len(x)*dbins). I guess the simplest way would be to simply change the yticklabels (by dividing them by len(x)). The thing is that I simply cannot find out how to do this...

I tried using the axes.set_yticklabels() but doesn't work. I've also tried to find the child containing the label but couldn't find it (not in Axes, nor in YAxis etc...). I guess it must be a Text instance.

Can anyone give me a hint,

Cheers,

Aure

------------------------------------------------------------------------
Ne gardez plus qu'une seule adresse mail ! Copiez vos mails <http://fr.rd.yahoo.com/mail/mail_taglines/trueswitch/SIG=11gshn0bu/**http%3A%2F%2Fwww.trueswitch.com%2Fyahoo-fr%2F> vers Yahoo! Mail

------------------------------------------------------------------------

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/

------------------------------------------------------------------------

_______________________________________________
Matplotlib-users mailing list
Matplotlib-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/matplotlib-users

You can set your own custom tick formatter:

import matplotlib.ticker as ticker

N = len(x)
def fmt_percent(x, pos=None):
return '%1.2f'%(float(x)/N)

ax.xaxis.set_major_formatter(ticker.FuncFormatter(fmt_percent)). See
http://matplotlib.sourceforge.net/examples/custom_ticker1.py for a
complete example.

JDH

···

On Fri, Feb 22, 2008 at 7:52 AM, Auré Gourrier <aurelien.gourrier@...136...> wrote:

Rather trivial... but instead of the plotting the counts n, I'd like to plot
the realtive percentage counts, i.e. n/len(x). I can't really use the option
normed = 1 which plots n/(len(x)*dbins). I guess the simplest way would be
to simply change the yticklabels (by dividing them by len(x)). The thing is
that I simply cannot find out how to do this...

I tried using the axes.set_yticklabels() but doesn't work. I've also tried
to find the child containing the label but couldn't find it (not in Axes,
nor in YAxis etc...). I guess it must be a Text instance.