gnuplot-py-users Mailing List for Gnuplot.py

David,

Thanks for your email.  Obviously you figured out one way to print to a 
file.

I was working on generic support for gnuplot terminals and the code is 
checked into CVS.  If you are willing to install Gnuplot.py from CVS you 
can try it out.  I've defined a mechanism in termdefs.py for defining 
terminal options, and I've typed the list of options for a few terminal 
types into that file (including png).  It would be easy for you to add 
the information about other terminal types that you want to use, and 
then the Gnuplot.hardcopy() method will be able to work the them. 
 Unfortunately the only documentation is in the source file, which is 
one reason that I haven't released a version including this new code :-( 
 The other, main reason is that I haven't had time to work on Gnuplot.py 
in quite a while. :-( :-(

You might run into the famous "temporary-file deletion" problem if you 
try to use your script in an automated environment.  See the archives of 
this newsgroup and FAQS.txt in the CVS repository of Gnuplot.py for more 
information.

Regarding the jpeg and gif support: jpeg should work (afaik) though 
since it is lossy it is not ideal for output such as that produced by 
gnuplot.  (You will especially notice that the large white background 
regions are not uniform.)  PNG is the recommended output format if it 
can be used by the rest of your tools.  Jpeg support is compiled into 
the gnuplot packaged with RedHat Linux but it is possible that you have 
to recompile gnuplot to enable support for it.

I don't believe that gnuplot supports GIF anymore because GIF is a 
proprietary format and to write GIF files requires paying a license fee 
to somebody.  But see the gnuplot web site or user groups for the latest 
information on that topic.

Yours,
Michael

David Casti wrote:

>On 1/10/03 8:32 AM, "David Casti" <da...@ne...> wrote:
>
>>My question: how do I get the output of gnuplot to go into a gif, png or
>>jpeg file?  I believe I have compiled and installed all of the correct
>>components to make this possible... but I just don't know where to throw the
>>switch.  Can someone give me a quick pointer?
>>    
>>
>
>I asked too soon... turns out this is not hard at all --
>
>import Gnuplot, Gnuplot.funcutils
>g = Gnuplot.Gnuplot( debug=1 )
>g('set term png')
>g('set output "/tmp/david.png"')
>g.plot( [ [0, 1], [1, 2], [2, 3], [3, 4] ] )
>  
>

-- 
Michael Haggerty
mh...@al...

On 1/10/03 8:32 AM, "David Casti" <da...@ne...> wrote:

> My question: how do I get the output of gnuplot to go into a gif, png or
> jpeg file?  I believe I have compiled and installed all of the correct
> components to make this possible... but I just don't know where to throw the
> switch.  Can someone give me a quick pointer?

I asked too soon... turns out this is not hard at all --

import Gnuplot, Gnuplot.funcutils
g = Gnuplot.Gnuplot( debug=1 )
g('set term png')
g('set output "/tmp/david.png"')
g.plot( [ [0, 1], [1, 2], [2, 3], [3, 4] ] )

-- and observe the output file in /tmp/david.png.

It appears that jpeg and gif support is going to be trickier... because "set
terminal" at the gnuplot command prompt does not show those to be available
terminal types.  Once I figure out how to make them available, the way to
use them in gnuplot.py is clear.

I hope this post helps a future gnuplot.py user!  :)
David.

Hello,

I have just come across gnuplot, and am very pleased to discover the python
interface.  Everything appears to be set up here correctly... the demo
charts are outstanding.

My question: how do I get the output of gnuplot to go into a gif, png or
jpeg file?  I believe I have compiled and installed all of the correct
components to make this possible... but I just don't know where to throw the
switch.  Can someone give me a quick pointer?

Thanks,
David.

Thanks to everyone for the input.  Turned out that adding the path to 
gnuplot in the bash script that was calling the gnuplot.py routine which 
is all being called from a cron entry did the trick.

Thanks again,
mtc

Michael Haggerty wrote:

> Hi,
>
> My guess is that "gnuplot: not found" indicates that the gnuplot 
> program (not the Python package but the program itself) is not in your 
> PATH.
>
> If that is not the case, make sure that you don't have problems with 
> temporary files being deleted before they are used.  The FAQ.txt file 
> in the latest CVS version of Gnuplot.py has more information about 
> this well-known problem.
>
> If you are interested in Gnuplot.py issues, you might consider 
> subscribing to the mailing list.  You can do that through SourceForge,
>
>    http://sourceforge.net/projects/gnuplot-py
>
> Let me know if it helps,
> Michael
>
> Michael T. Colee wrote:
>
>> Hello and thanks for the efforts on gnuplot.py, really a nice tool.  
>> I'm hoping you might have some insight into a problem I'm having as a 
>> relatively new python and gnuplot.py user.
>>
>> I've written a rather brute force script that generates png plots  of 
>> various meteorological fields for posting on a web page.  When I run 
>> it from the command line it functions beautifully and generates all 
>> my plots in the locations I want them.  If you are curious to see the 
>> results what I'm doing you can look at:
>>
>> http://neige.bren.ucsb.edu/mmsa/images/weekly/default.htm
>> &
>> http://neige.bren.ucsb.edu/mmsa/images/daily/default.htm
>>
>> When I go to run the routine scheduled from a cron entry however, it 
>> chokes.  The system I'm on is running W2K server and I've got cron 
>> running under cygwin which calls various scripts every hour to 
>> generate the pages I need.  Other python scripts work fine in this 
>> manner, for example, the following page:
>>
>> http://neige.bren.ucsb.edu/mmsa/images/hourly/LatestMet.htm
>>
>> is automatically generated hourly from a seperate python script 
>> called from the same cron entry.
>>
>> So, the code (Plotmmsa.py) I'm having trouble with is:
>>
>> _________________________________________________________
>> #...bunch of prep stuff cut out for brevity...
>> print "Read in and set various lists, starting plots. Last depth 
>> reading:"
>> print PlatformTemp[-1:] #make sure we've got data in our lists (we do).
>>
>> #g = Gnuplot.Gnuplot()
>> g = Gnuplot.Gnuplot(debug=1) #debug=1 outputs gnuplot commands to stdout
>> g('set data style lines')
>> #g('set data style linespoints')
>> g('set term png color')
>>
>>
>> g.title('Temperature')
>> g.xlabel('Day of Year')
>> g.ylabel('Degrees C')
>> #This is line 106 which seems to be the problem:
>> g('set output "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"')
>> g.plot(PlatformTemp[-700:]) #Plot the last 7 days of data.
>> time.sleep(1)        #Wait for gnuplot to do it's thing.
>> g('set output "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"')
>> g.plot(PlatformTemp[-96:])  #Plot the last day of data.
>> time.sleep(1)        #Wait for gnuplot to do it's thing.
>> #...Rest of plots left out for brevity...
>> __________________________________________________________
>>
>>
>> Output from running Plotmmsa.py at the command prompt:
>>
>> $ ../bin/python/Plotmmsa.py
>> Read in and set various lists, starting plots. Last depth reading:
>> [[7.458333333333333, 3.8610000000000002]]
>> gnuplot> set data style lines
>> gnuplot> set term png color
>> gnuplot> set title "Temperature"
>> gnuplot> set xlabel "Day of Year"
>> gnuplot> set ylabel "Degrees C"
>> gnuplot> set output 
>> "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"
>> gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1648.0' notitle
>> gnuplot> set output 
>> "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"
>> gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1648.1' notitle
>> __________________________________________________________
>>
>> Output from cron running the same program:
>>
>> gnuplot> set data style lines
>> gnuplot> set term png color
>> gnuplot> set title "Temperature"
>> gnuplot> set xlabel "Day of Year"
>> gnuplot> set ylabel "Degrees C"
>> gnuplot> set output 
>> "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"
>> gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1984.0' notitle
>> gnuplot: not found
>> Read in and set various lists, starting plots. Last depth reading:
>> [[7.458333333333333, 3.8610000000000002]]
>> Traceback (most recent call last):
>>   File "/home/mmsa/bin/python/Plotmmsa.py", line 106, in ?
>>     g('set output 
>> "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"')
>>   File "/usr/lib/python2.2/site-packages/Gnuplot/_Gnuplot.py", line 
>> 206, in __call__
>>     self.gnuplot(s)
>>   File "/usr/lib/python2.2/site-packages/Gnuplot/gp_unix.py", line 
>> 203, in __call__
>>     self.flush()
>> IOError: [Errno 32] Broken pipe
>>
>> _________________________________________________________
>>
>> Any suggestions would be much appreciated.  My next step will be to 
>> get gnuplot.py running on a linux box and see if I have the same 
>> problems there.
>>
>> Thanks in advance,
>> mtc
>>
>
>

-- 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Michael Colee                        Internet: mt...@ic...
ICESS & Bren SESM                    Phone   : (805) 893-2883
University of California             Fax     : (805) 893-6113
Santa Barbara CA 93106-3060          Office  : 1001 Bren Hall
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

Michael:

> When I go to run the routine scheduled from a cron entry however, it=20
> chokes.  The system I'm on is running W2K server and I've got cron=20
> running under cygwin which calls various scripts every hour=20
> to generate the pages I need.

> #This is line 106 which seems to be the problem:
> g('set output "/home/blabla/out.png"')

I guess, the problem is not so much with Python and Gnuplot, but rather
with the interaction of W2K, Cygwin, and cron. It looks to me as if
your cron job simply doesn't know about the Cygwin file name mapping.
Try with a little test script. Alternatively, try with "Windows" (i.e.
DOS) file names "D:\cygwin\home\blabla\out.png".

Good luck, Joachim

Hi,

My guess is that "gnuplot: not found" indicates that the gnuplot program 
(not the Python package but the program itself) is not in your PATH.

If that is not the case, make sure that you don't have problems with 
temporary files being deleted before they are used.  The FAQ.txt file in 
the latest CVS version of Gnuplot.py has more information about this 
well-known problem.

If you are interested in Gnuplot.py issues, you might consider 
subscribing to the mailing list.  You can do that through SourceForge,

    http://sourceforge.net/projects/gnuplot-py

Let me know if it helps,
Michael

Michael T. Colee wrote:

> Hello and thanks for the efforts on gnuplot.py, really a nice tool.  
> I'm hoping you might have some insight into a problem I'm having as a 
> relatively new python and gnuplot.py user.
>
> I've written a rather brute force script that generates png plots  of 
> various meteorological fields for posting on a web page.  When I run 
> it from the command line it functions beautifully and generates all my 
> plots in the locations I want them.  If you are curious to see the 
> results what I'm doing you can look at:
>
> http://neige.bren.ucsb.edu/mmsa/images/weekly/default.htm
> &
> http://neige.bren.ucsb.edu/mmsa/images/daily/default.htm
>
> When I go to run the routine scheduled from a cron entry however, it 
> chokes.  The system I'm on is running W2K server and I've got cron 
> running under cygwin which calls various scripts every hour to 
> generate the pages I need.  Other python scripts work fine in this 
> manner, for example, the following page:
>
> http://neige.bren.ucsb.edu/mmsa/images/hourly/LatestMet.htm
>
> is automatically generated hourly from a seperate python script called 
> from the same cron entry.
>
> So, the code (Plotmmsa.py) I'm having trouble with is:
>
> _________________________________________________________
> #...bunch of prep stuff cut out for brevity...
> print "Read in and set various lists, starting plots. Last depth 
> reading:"
> print PlatformTemp[-1:] #make sure we've got data in our lists (we do).
>
> #g = Gnuplot.Gnuplot()
> g = Gnuplot.Gnuplot(debug=1) #debug=1 outputs gnuplot commands to stdout
> g('set data style lines')
> #g('set data style linespoints')
> g('set term png color')
>
>
> g.title('Temperature')
> g.xlabel('Day of Year')
> g.ylabel('Degrees C')
> #This is line 106 which seems to be the problem:
> g('set output "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"')
> g.plot(PlatformTemp[-700:]) #Plot the last 7 days of data.
> time.sleep(1)        #Wait for gnuplot to do it's thing.
> g('set output "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"')
> g.plot(PlatformTemp[-96:])  #Plot the last day of data.
> time.sleep(1)        #Wait for gnuplot to do it's thing.
> #...Rest of plots left out for brevity...
> __________________________________________________________
>
>
> Output from running Plotmmsa.py at the command prompt:
>
> $ ../bin/python/Plotmmsa.py
> Read in and set various lists, starting plots. Last depth reading:
> [[7.458333333333333, 3.8610000000000002]]
> gnuplot> set data style lines
> gnuplot> set term png color
> gnuplot> set title "Temperature"
> gnuplot> set xlabel "Day of Year"
> gnuplot> set ylabel "Degrees C"
> gnuplot> set output 
> "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"
> gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1648.0' notitle
> gnuplot> set output 
> "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"
> gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1648.1' notitle
> __________________________________________________________
>
> Output from cron running the same program:
>
> gnuplot> set data style lines
> gnuplot> set term png color
> gnuplot> set title "Temperature"
> gnuplot> set xlabel "Day of Year"
> gnuplot> set ylabel "Degrees C"
> gnuplot> set output 
> "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"
> gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1984.0' notitle
> gnuplot: not found
> Read in and set various lists, starting plots. Last depth reading:
> [[7.458333333333333, 3.8610000000000002]]
> Traceback (most recent call last):
>   File "/home/mmsa/bin/python/Plotmmsa.py", line 106, in ?
>     g('set output 
> "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"')
>   File "/usr/lib/python2.2/site-packages/Gnuplot/_Gnuplot.py", line 
> 206, in __call__
>     self.gnuplot(s)
>   File "/usr/lib/python2.2/site-packages/Gnuplot/gp_unix.py", line 
> 203, in __call__
>     self.flush()
> IOError: [Errno 32] Broken pipe
>
> _________________________________________________________
>
> Any suggestions would be much appreciated.  My next step will be to 
> get gnuplot.py running on a linux box and see if I have the same 
> problems there.
>
> Thanks in advance,
> mtc
>


-- 
Michael Haggerty
mh...@al...

Hello and thanks for the efforts on gnuplot.py, really a nice tool.  I'm 
hoping you might have some insight into a problem I'm having as a 
relatively new python and gnuplot.py user.

I've written a rather brute force script that generates png plots  of 
various meteorological fields for posting on a web page.  When I run it 
from the command line it functions beautifully and generates all my 
plots in the locations I want them.  If you are curious to see the 
results what I'm doing you can look at:

http://neige.bren.ucsb.edu/mmsa/images/weekly/default.htm
&
http://neige.bren.ucsb.edu/mmsa/images/daily/default.htm

When I go to run the routine scheduled from a cron entry however, it 
chokes.  The system I'm on is running W2K server and I've got cron 
running under cygwin which calls various scripts every hour to generate 
the pages I need.  Other python scripts work fine in this manner, for 
example, the following page:

http://neige.bren.ucsb.edu/mmsa/images/hourly/LatestMet.htm

is automatically generated hourly from a seperate python script called 
from the same cron entry.

So, the code (Plotmmsa.py) I'm having trouble with is:

_________________________________________________________
#...bunch of prep stuff cut out for brevity...
print "Read in and set various lists, starting plots. Last depth reading:"
print PlatformTemp[-1:] #make sure we've got data in our lists (we do).

#g = Gnuplot.Gnuplot()
g = Gnuplot.Gnuplot(debug=1) #debug=1 outputs gnuplot commands to stdout
g('set data style lines')
#g('set data style linespoints')
g('set term png color')


g.title('Temperature')
g.xlabel('Day of Year')
g.ylabel('Degrees C')
#This is line 106 which seems to be the problem:
g('set output "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"')
g.plot(PlatformTemp[-700:]) #Plot the last 7 days of data.
time.sleep(1)		#Wait for gnuplot to do it's thing.
g('set output "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"')
g.plot(PlatformTemp[-96:])  #Plot the last day of data.
time.sleep(1)		#Wait for gnuplot to do it's thing.
#...Rest of plots left out for brevity...
__________________________________________________________


Output from running Plotmmsa.py at the command prompt:

$ ../bin/python/Plotmmsa.py
Read in and set various lists, starting plots. Last depth reading:
[[7.458333333333333, 3.8610000000000002]]
gnuplot> set data style lines
gnuplot> set term png color
gnuplot> set title "Temperature"
gnuplot> set xlabel "Day of Year"
gnuplot> set ylabel "Degrees C"
gnuplot> set output "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"
gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1648.0' notitle
gnuplot> set output "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"
gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1648.1' notitle
__________________________________________________________

Output from cron running the same program:

gnuplot> set data style lines
gnuplot> set term png color
gnuplot> set title "Temperature"
gnuplot> set xlabel "Day of Year"
gnuplot> set ylabel "Degrees C"
gnuplot> set output "/home/mmsa/wwwroot/mmsa/images/weekly/PlatformTemp.png"
gnuplot> plot '/cygdrive/c/WINNT/TEMP/@1984.0' notitle
gnuplot: not found
Read in and set various lists, starting plots. Last depth reading:
[[7.458333333333333, 3.8610000000000002]]
Traceback (most recent call last):
   File "/home/mmsa/bin/python/Plotmmsa.py", line 106, in ?
     g('set output "/home/mmsa/wwwroot/mmsa/images/daily/PlatformTemp.png"')
   File "/usr/lib/python2.2/site-packages/Gnuplot/_Gnuplot.py", line 
206, in __call__
     self.gnuplot(s)
   File "/usr/lib/python2.2/site-packages/Gnuplot/gp_unix.py", line 203, 
in __call__
     self.flush()
IOError: [Errno 32] Broken pipe

_________________________________________________________

Any suggestions would be much appreciated.  My next step will be to get 
gnuplot.py running on a linux box and see if I have the same problems there.

Thanks in advance,
mtc

-- 
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Michael Colee                        Internet: mt...@ic...
ICESS & Bren SESM                    Phone   : (805) 893-2883
University of California             Fax     : (805) 893-6113
Santa Barbara CA 93106-3060          Office  : 1001 Bren Hall
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=