fixed v=0 loglocator bug

svn path=/trunk/matplotlib/; revision=932

Author: jdh2358

lib/matplotlib/ticker.py

@@ -646,9 +646,8 @@ def autoscale(self):
         minpos = self.dataInterval.minpos()
         if minpos<0:
             raise RuntimeError('No positive data to plot')
-        if vmin<0:
+        if vmin<=0:
             vmin = minpos
-         
         if not is_decade(vmin,self.base): vmin = decade_down(vmin,self.base)
         if not is_decade(vmax,self.base): vmax = decade_up(vmax,self.base)
         if vmin==vmax: