Hi, I'd like to plot my data and indicate where the

> instrument I used actually actually should truncate

> those data. My idea is to have y values from zero to a

> certain maximum and to draw a red line from zero to the

> lower limit, then to continue with this line colored in

> black, and finally end this very line colored red from

> the upper limit to the maximum of my data. How is this

> to accomplish?

Sorry for the delay in answering this. I am not 100% sure I

understand your question, but it appears to me that you want to color

a line differently depending on it's y value. You can do this with

masked arrays, which are supported in matplotlib CVS

import matplotlib.numerix.ma as ma

from matplotlib.numerix import logical_or

from pylab import plot, show, arange, sin, pi

t = arange(0.0, 2.0, 0.01)

s = sin(2*pi*t)

upper = 0.77

lower = -0.77

supper = ma.masked_where(s < upper, s)

slower = ma.masked_where(s > lower, s)

smiddle = ma.masked_where(logical_or(s<lower, s>upper), s)

plot(t, slower, 'r', t, smiddle, 'b', t, supper, 'g')

show()

Another approach, which will work with any recent matplotlib

(including 0.71), is to use a shaded region to indicate your ranges.

from pylab import plot, show, arange, sin, pi, axhspan

t = arange(0.0, 2.0, 0.01)

s = sin(2*pi*t)

upper = 0.77

lower = -0.77

plot(t, s)

axhspan(upper, 1, facecolor='red', alpha=0.5)

axhspan(-1, lower, facecolor='blue', alpha=0.5)

show()

> A second problem for me is probably trivial for more

> experienced users: How to adjust the size of x- &

> y-labels (using subplot)?

> I should mention that I'm stuck with version 0.71 for a

> while ...

xlabel('my label', fontsize=16)

You can also control the default x and y label size, and the tick

label size, in your rc file

http://matplotlib.sourceforge.net/.matplotlibrc

To set the fontsize for the tick labels, you can do something like

locs, labels = xticks()

set(labels, fontsize=16)

Should help!

JDH