ENH added offset to NewDateFormatter; some minor fixes

jklymak · jklymak · commit 179c28ef3880 · 2018-03-20T14:26:42.000-07:00
diff --git a/lib/matplotlib/dates.py b/lib/matplotlib/dates.py
@@ -780,7 +780,8 @@ class NewDateFormatter(ticker.Formatter):
 
     """
 
-    def __init__(self, locator, tz=None, defaultfmt='%Y-%h-%d %H:%M:%S'):
+    def __init__(self, locator, tz=None, defaultfmt='%Y-%h-%d %H:%M:%S',
+            show_offset=True):
         """
         Autoformat the date labels.  The default format is used to form an
         initial string, and then redundant elements are removed.
@@ -797,21 +798,24 @@ def __init__(self, locator, tz=None, defaultfmt='%Y-%h-%d %H:%M:%S'):
         self._hourfmt = '%H'
         self._minutefmt = '%M'
         self._secondfmt = '%S'
+        self.offset_string = 'Dates!'
+        self.show_offset = show_offset
 
     def __call__(self, x, pos=None):
         locator_unit_scale = float(self._locator._get_unit())
         dmin, dmax = self._locator.viewlim_to_dt()
+
         ticks = self._locator.tick_values(dmin, dmax)
         if pos is not None:
             if not np.array_equal(ticks, self._oldticks):
 
+                offset_fmt = ''
                 fmt = self.defaultfmt
                 self._formatter = DateFormatter(fmt, self._tz)
                 tickdate = []
 
                 for nn, tick in enumerate(ticks):
                     tickdate += [num2date(tick)]
-                print(tickdate)
                 yearfmt = [self._yearfmt] * len(tickdate)
                 monthfmt = [self._monthfmt] * len(tickdate)
                 dayfmt = [self._dayfmt] * len(tickdate)
@@ -825,6 +829,8 @@ def __call__(self, x, pos=None):
                         yearfmt[nn] = ''
                     else:
                         diffed = True
+                if not diffed:
+                    offset_fmt += yearfmt[0]
                 if not diffed or tickdate[0].month != 1:
                     yearfmt[0] = ''
 
@@ -837,6 +843,9 @@ def __call__(self, x, pos=None):
                             monthfmt[nn] = ''
                         else:
                             diffed = True
+                    if not diffed:
+                        offset_fmt += '-' + monthfmt[0]
+                        monthfmt[0] = ''
                     if tickdate[0].day != 1:
                         monthfmt[0] = ''
                 else:
@@ -856,12 +865,16 @@ def __call__(self, x, pos=None):
                             dayfmt[nn] = ''
                         else:
                             diffed = True
+                    if not diffed:
+                        offset_fmt += '-' + dayfmt[0]
                     if not diffed or tickdate[0].hour != 0:
                         dayfmt[0] = ''
                 else:
                     for nn in range(0, len(tickdate)):
                         if tickdate[nn].day == 1:
                             dayfmt[nn] = ''
+                        if (tickdate[nn].day == tickdate[nn-1].day):
+                            dayfmt[nn] = ''
 
                 # remove extra seconds if all zero:
                 remove = True
@@ -896,6 +909,8 @@ def __call__(self, x, pos=None):
                         fmt += dayfmt[nn]
                         if not hourfmt[nn] == '':
                             fmt += ' '
+                    elif not monthfmt[nn] == '':
+                        fmt += ' '
                     if not hourfmt[nn] == '':
                         fmt += hourfmt[nn]
                         if not secondfmt[nn] == '':
@@ -907,11 +922,16 @@ def __call__(self, x, pos=None):
                 result = ticknew[pos]
                 self._oldticks = ticks
                 self._oldlabels = ticknew
+                if self.show_offset:
+                    self.offset_string = tickdate[-1].strftime(offset_fmt)
             result = self._oldlabels[pos]
         else:
             result = self._formatter(x, pos)
         return result
 
+    def get_offset(self):
+        return self.offset_string
+
 
 class AutoDateFormatter(ticker.Formatter):
     """
