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There is a package called PyQwt3D/Qwt3D that can be used.

Brian=20

-----Original Message-----
From: mat...@li...
[mailto:mat...@li...] On Behalf Of
Jonathan Taylor
Sent: Thursday, June 01, 2006 1:38 PM
To: matplotlib-users
Subject: [Matplotlib-users] 3d bar plots


Hi,

Was wondering if anyone knows if there was any way to reproduce this
kind of
example:

http://www.mps.mpg.de/dislin/exa_bars3d.html

i.e. a 3d barplot.

Thanks,

Jonathan

Hi,

Was wondering if anyone knows if there was any way to reproduce this kind of
example:

http://www.mps.mpg.de/dislin/exa_bars3d.html

i.e. a 3d barplot.

Thanks,

Jonathan

>>>>> "Marquardt," == Marquardt, Colin <col...@zm...> writes:


    Colin> Also, you are using some parameters (usecols, unpack) to
    Colin> load() that
    Colin> http://matplotlib.sourceforge.net/matplotlib.pylab.html#-load
    Colin> doesn't know about.


The web page is a bit out of date and needs updating -- thanks for the
pointers to the stale and broken links.  The "load" parameters used
here were recently introduced.  I suggest keeping an ipython shell
open when working with matplotlib, so you have ready access to the
online help 

In [1]: help load

load(fname, comments='%', delimiter=None, converters=None,
     skiprows=0, usecols=None, unpack=False):
    
    Load ASCII data from fname into an array and return the array.

    The data must be regular, same number of values in every row

    fname can be a filename or a file handle.  Support for gzipped
    files is automatic, if the filename ends in .gz

    matfile data is not currently supported, but see
    Nigel Wade's matfile ftp://ion.le.ac.uk/matfile/matfile.tar.gz

    Example usage:

      X = load('test.dat')  # data in two columns
      t = X[:,0]
      y = X[:,1]

    Alternatively, you can do the same with "unpack"; see below

      X = load('test.dat')    # a matrix of data
      x = load('test.dat')    # a single column of data

    comments - the character used to indicate the start of a comment
    in the file

    delimiter is a string-like character used to seperate values in the
    file. If delimiter is unspecified or None, any whitespace string is
    a separator.

    converters, if not None, is a dictionary mapping column number to
    a function that will convert that column to a float.  Eg, if
    column 0 is a date string: converters={0:datestr2num}

    skiprows is the number of rows from the top to skip

    usecols, if not None, is a sequence of integer column indexes to
    extract where 0 is the first column, eg usecols=(1,4,5) to extract
    just the 2nd, 5th and 6th columns

    unpack, if True, will transpose the matrix allowing you to unpack
    into named arguments on the left hand side

        t,y = load('test.dat', unpack=True) # for  two column data
        x,y,z = load('somefile.dat', usecols=(3,5,7), unpack=True)

    See examples/load_demo.py which exeercises many of these options.
    

John Hunter <jdh...@ni...> writes:

> The function datestr2num takes any date string recognized by
> dateutils.parse (most of them) and returns a floating point number
> days since 0000-00-00 which is how matplotlib represents dates.

Wow, matplotlib is even cooler than I thought :)

Let me report some small issues I found (not meant as a rant):

http://matplotlib.sourceforge.net/matplotlib.dates.html refers
to https://moin.conectiva.com.br/DateUtil but this page now resides
at http://labix.org/python-dateutil.

Also, you are using some parameters (usecols, unpack) to load() that
http://matplotlib.sourceforge.net/matplotlib.pylab.html#-load doesn't
know about.

The links for "matplotlib._pylab_helpers", "matplotlib.backends and
"matplotlib" in the "Modules" section of
http://matplotlib.sourceforge.net/matplotlib.pylab.html don't work.

> We have steps too!
>
>   plot(x, y, linestyle=3D'steps')

Oh, I must have overlooked that. I need to remember that
users_guide_0.87.1.pdf doesn't cover everything...

Thanks,
  Colin

Christopher Barker wrote:
> Louis,
>
> This is standard num* array behavior: arrays are mutable, and MPL is 
> not making copies of them when you plot, which is a good thing.
>
> by the way, slices of arrays are references too, which is different 
> than python lists, so it can be surprising, but also useful
>
>>              # 1st Plot .................
>>        x[0]= 1.0
>>        y[0]= 1.0
>>        x[1]=-1.0
>>        y[1]=-1.0
>>        a.plot(x,y)
>>
>>        # 2nd Plot .................
>
> now you need copies. You can make brand new ones, or use the copy() 
> method:
> x = x.copy()
> y = y.copy()
>
> you could also pass a copy into the plot method:
>
> a.plot(x.copy(), y.copy())
>
> which is perhaps the behavior you were expecting.
>
> -Chris

Thanks, Chris.  I sort of figured this out, but you put it clearer and I 
like the copy suggestion.  I'll use it.  It sure drove me nuts for a 
while.  :-)

-- 
Cheers,

Lou Pecora

Code 6362
Naval Research Lab
Washington, DC  20375
USA
Ph:  +202-767-6002
email:  pe...@an...

Louis,

This is standard num* array behavior: arrays are mutable, and MPL is not 
making copies of them when you plot, which is a good thing.

by the way, slices of arrays are references too, which is different than 
python lists, so it can be surprising, but also useful

>              # 1st Plot .................
>        x[0]= 1.0
>        y[0]= 1.0
>        x[1]=-1.0
>        y[1]=-1.0
>        a.plot(x,y)
> 
>        # 2nd Plot .................

now you need copies. You can make brand new ones, or use the copy() method:
x = x.copy()
y = y.copy()

you could also pass a copy into the plot method:

a.plot(x.copy(), y.copy())

which is perhaps the behavior you were expecting.

-Chris


-- 
Christopher Barker, Ph.D.
Oceanographer
                                     		
NOAA/OR&R/HAZMAT         (206) 526-6959   voice
7600 Sand Point Way NE   (206) 526-6329   fax
Seattle, WA  98115       (206) 526-6317   main reception

Chr...@no...

Bill Dandreta <wjd...@at...> writes:

> Here's a code snippet I found somewhere that demonstrates the use:

Thanks Jonathan and Bill, that works fine.

Cheers,
  Colin

>>>>> "Marquardt," == Marquardt, Colin <col...@zm...> writes:


    Colin> * My data file consists of a date (in ISO format) and
    Colin> integers. Parsing the date was a bit of work. I
    Colin> understand that python's datetime doesn't provide any
    Colin> parsing of dates - but maybe matplotlib should have
    Colin> some functions for that then?  FWIW, here is how
    Colin> gnuplot does this (adapted from
    Colin> http://t16web.lanl.gov/Kawano/gnuplot/datetime-e.html):

    Colin>      set xdata time set timefmt "%Y-%m-%d" set format
    Colin> x "%Y-%m"

gnuplot does handle file plots nicely -- here is an example of how to
parse files with date entries and plot them in matplotlib.  Basically,
the load function takes a dictionary mapping column index to a
converter function which returns a float.

    from pylab import figure, show, datestr2num, load
    dates, closes = load(
        'data/msft.csv', delimiter=',',
        converters={0:datestr2num}, skiprows=1, usecols=(0,2),
        unpack=True)

    fig = figure()
    ax = fig.add_subplot(111)
    ax.plot_date(dates, closes)
    show()


The function datestr2num takes any date string recognized by
dateutils.parse (most of them) and returns a floating point number
days since 0000-00-00 which is how matplotlib represents dates.

    Colin> * gnuplot has a plot style "steps"
    Colin> (http://t16web.lanl.gov/Kawano/gnuplot/intro/style-e.html)
    Colin> - I could only fake that with with extra "dummy"
    Colin> points in matplotlib as I understand it. It would be
    Colin> nice if matplotlib could do this for me.

We have steps too!

  plot(x, y, linestyle='steps')


Hope this helps,
JDH

Here's a code snippet I found somewhere that demonstrates the use:

def make_datetime(s, fmt='%Y-%m-%d %H:%M'):
     '''convert string to datetime'''
     ts = time.mktime(time.strptime(s, fmt))
     return datetime.fromtimestamp(ts)

Warning, this is very slow, if you need to do a lot of conversions it 
will take some time.

Bill

Jonathan Taylor wrote:

> You can use python's time module to parse dates, see time.strptime and 
> time.strftime.
>
> Jonathan
>
> Marquardt, Colin wrote:
>
>> [Repost, sorry if you get this twice.]
>>
>> Hi guys,
>>
>> in my quest for a better gnuplot replacement, I came across matplotlib
>> yesterday.
>>
>> I really like it, big thanks to the developers.
>>
>> It was pretty easy to port over a gnuplot command file.  There are
>> two things that could have been easier still though:
>>
>> * My data file consists of a date (in ISO format) and integers. Parsing
>>   the date was a bit of work. I understand that python's datetime 
>> doesn't
>>   provide any parsing of dates - but maybe matplotlib should have some
>>   functions for that then?  FWIW, here is how gnuplot does this (adapted
>>   from http://t16web.lanl.gov/Kawano/gnuplot/datetime-e.html):
>>
>>      set xdata time
>>      set timefmt "%Y-%m-%d"
>>      set format x "%Y-%m"
>>
>>   In my matplotlib script, I'm now doing:
>>
>>      mydate = [int(elem) for elem in vals_line[0].split('-')]
>>      datenums.append(date2num(datetime.date(mydate[0], mydate[1], 
>> mydate[2])))
>>      [...]
>>      plotline = plot_date(datenums, data)
>>
>> * gnuplot has a plot style "steps"
>>   (http://t16web.lanl.gov/Kawano/gnuplot/intro/style-e.html) - I
>>   could only fake that with with extra "dummy" points in matplotlib
>>   as I understand it. It would be nice if matplotlib could do this
>>   for me.
>>
>> Cheers,
>>   Colin
>>
>

You can use python's time module to parse dates, see time.strptime and 
time.strftime.

Jonathan

Marquardt, Colin wrote:

> [Repost, sorry if you get this twice.]
>
> Hi guys,
>
> in my quest for a better gnuplot replacement, I came across matplotlib
> yesterday.
>
> I really like it, big thanks to the developers.
>
> It was pretty easy to port over a gnuplot command file.  There are
> two things that could have been easier still though:
>
> * My data file consists of a date (in ISO format) and integers. Parsing
>   the date was a bit of work. I understand that python's datetime doesn't
>   provide any parsing of dates - but maybe matplotlib should have some
>   functions for that then?  FWIW, here is how gnuplot does this (adapted
>   from http://t16web.lanl.gov/Kawano/gnuplot/datetime-e.html):
>
>      set xdata time
>      set timefmt "%Y-%m-%d"
>      set format x "%Y-%m"
>
>   In my matplotlib script, I'm now doing:
>
>      mydate = [int(elem) for elem in vals_line[0].split('-')]
>      datenums.append(date2num(datetime.date(mydate[0], mydate[1], 
> mydate[2])))
>      [...]
>      plotline = plot_date(datenums, data)
>
> * gnuplot has a plot style "steps"
>   (http://t16web.lanl.gov/Kawano/gnuplot/intro/style-e.html) - I
>   could only fake that with with extra "dummy" points in matplotlib
>   as I understand it. It would be nice if matplotlib could do this
>   for me.
>
> Cheers,
>   Colin
>

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[Repost, sorry if you get this twice.]

Hi guys,

in my quest for a better gnuplot replacement, I came across matplotlib
yesterday.

I really like it, big thanks to the developers.=20

It was pretty easy to port over a gnuplot command file.  There are
two things that could have been easier still though:

* My data file consists of a date (in ISO format) and integers. Parsing
  the date was a bit of work. I understand that python's datetime =
doesn't
  provide any parsing of dates - but maybe matplotlib should have some
  functions for that then?  FWIW, here is how gnuplot does this (adapted
  from http://t16web.lanl.gov/Kawano/gnuplot/datetime-e.html):

     set xdata time
     set timefmt "%Y-%m-%d"
     set format x "%Y-%m"

  In my matplotlib script, I'm now doing:

     mydate =3D [int(elem) for elem in vals_line[0].split('-')]
     datenums.append(date2num(datetime.date(mydate[0], mydate[1], =
mydate[2])))
     [...]
     plotline =3D plot_date(datenums, data)

* gnuplot has a plot style "steps"
  (http://t16web.lanl.gov/Kawano/gnuplot/intro/style-e.html) - I
  could only fake that with with extra "dummy" points in matplotlib
  as I understand it. It would be nice if matplotlib could do this
  for me.

Cheers,
  Colin

http://matplotlib.sourceforge.net/fonts.html:
> See font_properties_demo.py =
<http://matplotlib.sourceforge.net/examples/font_properties_demo.py>=20

*click*

An error has been encountered in accessing this page.=20

1. Server: matplotlib.sourceforge.net
2. URL path: /examples/font_properties_demo.py
3. Error notes: File does not exist: =
/home/groups/m/ma/matplotlib/htdocs/examples/font_properties_demo.py
4. Error type: 404
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6. Request query string:=20
7. Time: 2006-06-01 04:50:44 PDT (1149162644)