Realtime interactive graphing of a simulation

[sydneytroz]

I am writing a program to simulate a double displacement reaction getting to equilibrium, but I am having some trouble graphing the particles' concentrations. It seems that it's only possible to pan and zoom the graph once the program exits (when running it from IDLE), but I don't want to have to kill the sim every time I want to view the graph (besides, when I do, the graph window dissappears).

The following code contains all the graphing functionality, the initGraph() function is called before the sim's main loop, and updateGraph() is called once a second with the current concentrations of 4 types of particles. The sim uses PyGame for graphics, and I didn't think that code was relevant: if it is, just let me know and I'll post it.

[CODE=python]
from pylab import *

# Turn on interactive mode for graphing
ion()
#hold(False)
xlabel("time (seconds)")
ylabel("concent ration (particles/window)")

#graphLines = []
graphData = []
updateInterval = 0

def initGraph(inter val, *colours):
"""Initiali zes this module

interval: the time, in seconds, btwn calls to updateGraph()
colours: list of 3-tuples (r,g,b) for each line's colour
"""
updateInterval = interval
for c in colours:
line = plot([0],[0])[0]
line.set_color( c)
graphData.appen d({'x':[0],'y':[0]})
#graphLines.app end(line)

def updateGraph(*co ns):
"""Updates graph data and draws it

cons: a list of concentrations, the same length of colours arg to initGraph
"""
#for line, con in zip(graphLines, cons):
for line, con in zip(graphData, cons):
#xdata, ydata = line.get_xdata( ), line.get_ydata( )
#xdata.append(x data[-1] + updateInterval)
#ydata.append(c on)
#line.set_data( xdata, ydata)
#plot(xdata, ydata)
line['x'].append(line['x'][-1] + updateInterval)
line['y'].append(con)

plot(*[line['x'], line['y'] for line in graphData])
[/CODE]

[bartonc]

As much as I dislike globals, working on the module level like this, it is convenient:[CODE=python]
updateInterval = 0

def initGraph(inter val, *colours):
"""Initiali zes this module

interval: the time, in seconds, btwn calls to updateGraph()
colours: list of 3-tuples (r,g,b) for each line's colour
"""
global updateInterval
updateInterval = interval
for c in colours:
line = plot([0],[0])[0]
line.set_color( c)
graphData.appen d({'x':[0],'y':[0]})
#graphLines.app end(line)[/CODE]Otherwise, updateInterval remains a function-scope variable and nobody else sees the change.

That's the first thing that caught my eye... I'll keep looking.

[sydneytroz]

thanks, i appreciate your help