Re: [Matplotlib-users] Missing values in plots with NaN?

[Stephen W. <ste...@cs...>]

On Wed, 2004-08-18 at 15:02, Mark Howson wrote:
> Hi,
> 
> Is there any easy way of adding missing points to a (line) plot? Matlab 
> can do this using NaN, but as far as I can tell matplotlib doesn't 
> support this.

This would be very nice.  Gnuplot has a similar characteristic: to
create the plots at http://www.csun.edu/sfo, I use a trick like this:

f(x) = (x==-999999 ? 1/0 : x)
plot "file" using $1:(f($2))

so that an equally spaced time series appears with gaps where we have
missing data.

Hmmm...is this something which should be supported via masked arrays?  I
tried plotting a masked array with matplotlib and numarray's MA package,
and found matplotlib checks for the existence of a mask but throws an
exception if you try to plot it.