Re: [Matplotlib-users] Labels in a dynamic graph

[John H. <jd...@gm...>]

On Sun, Mar 23, 2008 at 3:54 AM, Amit Finkler <ami...@gm...> wrote:

> I am using matplotlib to dynamically plot a graph with both my x and y
> points taken from a measurement device. That is to say, in each iteration of
> my while loop I'm reading two variables which I then want to plot with
> matplotlib.

You will want to do something like (this is just a sketch)

xdata = []
ydata = []

fig = figure()
ax = fig.add_subplot(111)
ax.set_xlabel('my xlabel')
ax.set_ylabel('my ylabel')
line, = ax.plot(xdata, ydata)

def add_point(x, y):
    xdata.append(x)
    ydata.append(y)
    if len(xdata)>30:  # optional, prune the early points
        del xdata[0]
        del ydata[0]
    xmin = xdata[0]
    xmax = xdata[-1]
    line.set_data(xdata, ydata)
    ax.set_xlim(xmin, xmax)
    fig.canvas.draw()

while 1:
    x,y = get_data_point()
    add_point(x, y)

JDH