I have encountered several problems with plot_date. I am using 0.60.1 (maybe
fixed in 0.60.2?) on Solaris.

(1) If I put a smaller number as one of the dates (as seconds), it raises the
"before the epoch" error. But I think plot_date should accomodate dates earlier
than 1970.

t=[1.e7, 1.e8]

Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/usr/ra/pysoft/2.3.3/matplotlib/", line 1207, in plot_date
    try: lines = gca().plot_date(*args, **kwargs)
  File "/usr/ra/pysoft/2.3.3/matplotlib/", line 1496, in plot_date
    ret = self.plot(e, y, fmt, **kwargs)
  File "/usr/ra/pysoft/2.3.3/matplotlib/", line 1472, in plot
  File "/usr/ra/pysoft/2.3.3/matplotlib/", line 445, in autoscale_view
    tup = locator.autoscale()
  File "/usr/ra/pysoft/2.3.3/matplotlib/", line 728, in autoscale
    dmin = self.epochConverter.floor_month(dmin)
  File "/usr/ra/pysoft/2.3.3/matplotlib/", line 354, in floor_month
    if y<1970: raise RuntimeError('You are before the epoch!')
RuntimeError: You are before the epoch!

(2) After the error in (1) happens, even if I put "legal" dates and run
plot_date again, it still issues the same error. It seems there is some kind of
switch needs to be reset.

(3) if, e.g. t=[1.e8, 1.1e8], the x-axis tick labels are crowded.

JC Hsu