Re: [Gnuplot-py-users] help with splot & 3d data

[kevin p. <ke...@ma...>]

Michael Haggery,

Thanks for taking the time to respond. This is a very elegant and 
instructive. I like the way that you
set the styles in the styles dictionary. I would not have thought to do 
that. I wasn't aware that  the data
for Gnuplot.py, could also go into a separate file. That certainly 
makes for less cluttered code.

I have be playing and tweeking the code you sent and tried 'steps' and 
linesplots and changing the
grid. Everything works, but i wonder if there is not some more elegant 
way to represent this
data. I am wondering if there is a way to not only use plot, but splot?
Having x be the time (column 1), y be the value from column 2 and have 
z be the last value (column 4) and
then having the linespoints being not only a different style but spread 
out on the z axis to
boot. Perhaps that would be more salient?

Problem is, when i try to change:

items = [
    Gnuplot.Data(
        subsets[value],
        with=styles[value],
        using=(1,3,),
        )
    for value in values
    ]

g.plot(*items)

to use splot the whole thing barfs..... and i can't quite get my head 
around the splot entry in the
manual. I wonder if you could suggest an splot approach that is more 
visually clear.

It seems that splot is quite a different beast. In any case thanks for 
you instructions thus far. That is helpful handiwork
in that script, a real pea-shooter!

cheers,

kevin






On Nov 5, 2004, at 9:31 PM, Michael Haggerty wrote:

> kevin parks wrote:
>
>> I have data that looks like:
>>
>> 0 5.5 0 1
>> 2 5.5 2 4
>> 4 5.5 4 2
>> 6 5.5 5 3
>> 8 5.5 7 1
>> 10 5.5 9 4
>> 12 5.5 11 3
>> 14 5.5 0 2
>> 16 5.5 2 1
>> 18 5.5 4 4
>> 20 5.5 5 3
>
>
> It's easiest if you put your data into a file in the above format, 
> rather than typing it into Python as a list constant.
>
>> [...] I would like to use splot and points of different colors to 
>> convey as much info as i can. The X axis would be the time axis (that 
>> would take care of the first two parameters) and the Y axis could be 
>> the third column. Then for the fouth item, there are only four 
>> possibilities (1, 2, 3, or 4), so i thought that i could use points 
>> of red, blue, green, black to indicate that.
>
>
> I don't believe gnuplot offers a way to vary the style of points 
> depending on a data column, so I believe you should read the data into 
> Python, then use Python to pick it apart into four separate data sets, 
> then plot the four sets in one plot using four different data styles.  
> I believe the following script should do the trick.  It uses some 
> newer python features (2.2?) so parts might have to be changed if you 
> are using an older version of python.  Run it with the name of your 
> data file as command-line argument.
>
> |#! /usr/bin/env python
>
> import sys
> import Numeric
> import Gnuplot
>
> [filename] = sys.argv[1:]
>
> data = []
>
> for l in open(filename).readlines():
>    l = l.strip().split()
>    data.append([float(l[0]), float(l[1]), float(l[2]), int(l[3])])
>
> values = [1,2,3,4]
>
> # Here you can adjust the style options for each subset.  The
> # interpretation of the numbers depends on what "terminal" you are
> # using.
> styles = {
>    1 : 'points pt 1',
>    2 : 'points pt 2',
>    3 : 'points pt 3',
>    4 : 'points pt 4',
>    }
>
> subsets = {}
> for value in values:
>    subsets[value] = [l for l in data if l[3] == value]
>
> g = Gnuplot.Gnuplot()
> items = [
>    Gnuplot.Data(
>        subsets[value],
>        with=styles[value],
>        using=(1,3,),
>        )
>    for value in values
>    ]
>
> g.plot(*items)
>
> raw_input('Press enter to continue')
>
>
> Yours,
> Michael
> |
>
> -- 
> Michael Haggerty
> mh...@al...
>
>
>
> -------------------------------------------------------
> This SF.Net email is sponsored by:
> Sybase ASE Linux Express Edition - download now for FREE
> LinuxWorld Reader's Choice Award Winner for best database on Linux.
> http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click
> _______________________________________________
> Gnuplot-py-users mailing list
> Gnu...@li...
> https://lists.sourceforge.net/lists/listinfo/gnuplot-py-users