Histogram of floating point values.

Kurt Smith kwmsmith at gmail.com
Sat Jul 26 00:23:19 CEST 2008


On Fri, Jul 25, 2008 at 5:02 PM, aditya shukla
<adityashukla1983 at gmail.com> wrote:
> Hello folks,
>
> I have a list say
>
> data=[0.99,0.98,0.98,0.98,0.97,0.93,0.92,0.92,0.83,0.66,0.50,0.50]
>
> i am trying to plot histogram of these values
>
> i have installed numpy and matplotlib  and this is what i am doing*
>  import numpy
>  import pylab
>  from numpy import *
>  from pylab import *
>
> input_hist=array(data)
> pylab.hist(input_hist,bins=0.1)
> and this is the error that i am getting
>
> (array([], dtype=int32), array([ 0.5]), <a list of 0 Patch objects>)
>
>
> does this mean that i cannot plot a histogram of floating point values ? or
> is there a way around

the 'bins' argument to pylab.hist() is supposed to be an integer or a
list of the bins' lower edges.  The default value is 10, more than
that gives smaller bins, as one would expect.  Take a look at the
pylab.hist documentation (you can do 'print pylab.hist.__doc__' from
the command interpreter).

You should have no problem plotting a hist of floats.  Try this:

import numpy
import pylab
from numpy import *
from pylab import *

data=[0.99,0.98,0.98,0.98,0.97,0.93,0.92,0.92,0.83,0.66,0.50,0.50]

input_hist=array(data)
pylab.hist(input_hist)
pylab.show()

The last line will display the actual histogram.  See the difference
pylab.show and pylab.ion functions.

In the future, it is advisable to post these questions to the
matplotlib or the numpy/scipy users mailing lists.

Kurt



>
> Thanks in advance
>
> Aditya
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>



More information about the Python-list mailing list