Add convenience function, rcParams entry, for tick label format control

svn path=/trunk/matplotlib/; revision=2935

Author: efiring

CHANGELOG

@@ -1,3 +1,9 @@
+2006-12-17 Added rc param 'axes.formatter.limits' to control
+           the default threshold for switching to scientific
+           notation. Added convenience method
+           Axes.ticklabel_format() for turning scientific notation
+           on or off on either or both axes. - EF
+
 2006-12-16 Added ability to turn control scientific notation
            in ScalarFormatter - EF
 

lib/matplotlib/__init__.py

@@ -459,7 +459,7 @@ def validate_float(s):
         raise ValueError('Could not convert "%s" to float' % s)
 
 def validate_int(s):
-    'convert s to float or raise'
+    'convert s to int or raise'
     try: return int(s)
     except ValueError:
         raise ValueError('Could not convert "%s" to int' % s)
@@ -507,6 +507,19 @@ def __call__(self, s):
         except ValueError:
             raise ValueError('Could not convert all entries to floats')
 
+class validate_nseq_int:
+    def __init__(self, n):
+        self.n = n
+    def __call__(self, s):
+        'return a seq of n ints or raise'
+        ss = s.split(',')
+        if len(ss) != self.n:
+            raise ValueError('You must use exactly %d comma separated values'%self.n)
+        try: return [int(val) for val in ss]
+        except ValueError:
+            raise ValueError('Could not convert all entries to ints')
+
+
 def validate_color(s):
     'return a valid color arg'
     if s.lower() == 'none': return 'None'
@@ -791,6 +804,11 @@ def __call__(self, s):
     'axes.grid'         : [False, validate_bool],   # display grid or not
     'axes.labelsize'    : [12, validate_fontsize], # fontsize of the x any y labels
     'axes.labelcolor'   : ['k', validate_color],    # color of axis label
+    'axes.formatter.limits' : [(-7, 7), validate_nseq_int(2)],
+                               # use scientific notation if log10
+                               # of the axis range is smaller than the
+                               # first or larger than the second
+
 
     'polaraxes.grid'         : [True, validate_bool],   # display polar grid or not
 

lib/matplotlib/axes.py

@@ -1199,6 +1199,45 @@ def grid(self, b=None, **kwargs):
         self.yaxis.grid(b, **kwargs)
     grid.__doc__ = grid.__doc__%artist.kwdocd
 
+    def ticklabel_format(self, **kwargs):
+        """
+        Convenience method for manipulating the ScalarFormatter
+        used by default for linear axes.
+
+        kwargs:
+            style = 'sci' (or 'scientific') or 'plain';
+                        plain turns off scientific notation
+            axis = 'x', 'y', or 'both'
+
+        Only the major ticks are affected.
+        If the method is called when the ScalarFormatter is not
+        the one being used, an AttributeError will be raised with
+        no additional error message.
+
+        Additional capabilities and/or friendlier error checking may be added.
+
+        """
+        style = kwargs.pop('style', '').lower()
+        axis = kwargs.pop('axis', 'both').lower()
+        if style[:3] == 'sci':
+            sb = True
+        elif style in ['plain', 'comma']:
+            sb = False
+            if style == 'plain':
+                cb = False
+            else:
+                cb = True
+                raise NotImplementedError, "comma style remains to be added"
+        elif style == '':
+            sb = None
+        else:
+            raise ValueError, "%s is not a valid style value"
+        if sb is not None:
+            if axis == 'both' or axis == 'x':
+                self.xaxis.major.formatter.set_scientific(sb)
+            if axis == 'both' or axis == 'y':
+                self.yaxis.major.formatter.set_scientific(sb)
+
     def set_axis_off(self):
         """
         turn off the axis
@@ -2252,7 +2291,7 @@ def plot_date(self, x, y, fmt='bo', tz=None, xdate=True, ydate=False,
         a DateLocator instance) and the default tick formatter to
         AutoDateFormatter (if the tick formatter is not already set to
         a DateFormatter instance).
-        
+
         Valid kwargs are Line2D properties:
 %(Line2D)s
 

lib/matplotlib/ticker.py

@@ -268,7 +268,7 @@ def __init__(self, useOffset=True, useMathText=False):
         self.orderOfMagnitude = 0
         self.format = ''
         self._scientific = True
-        self._powerlimits = (-3,4)
+        self._powerlimits = rcParams['axes.formatter.limits']
 
     def __call__(self, x, pos=None):
         'Return the format for tick val x at position pos'
@@ -285,7 +285,7 @@ def set_powerlimits(self, lims):
         '''
         Sets size thresholds for scientific notation.
 
-        e.g. xaxis.set_powerlimits((-3, 4)) sets the default in
+        e.g. xaxis.set_powerlimits((-3, 4)) sets the pre-2007 default in
         which scientific notation is used for numbers less than
         1e-3 or greater than 1e4.
         See also set_scientific().

matplotlibrc.template

@@ -139,8 +139,10 @@ numerix      : %(numerix)s  # numpy, Numeric or numarray
 #axes.labelsize      : 12      # fontsize of the x any y labels
 #axes.labelcolor     : black
 #axes.axisbelow      : False   # whether axis gridlines and ticks are below
-                              # the axes elements (lines, text, etc)  
-                      
+                              # the axes elements (lines, text, etc)
+#axes.formatter.limits : -7, 7 # use scientific notation if log10
+                               # of the axis range is smaller than the
+                               # first or larger than the second
 
 polaraxes.grid      : True    # display grid on polar axes