use named entities instead of raw unicode codes

Author: afvincent

examples/api/engineering_formatter.py

@@ -34,8 +34,8 @@
 # Demo of the options `places` (number of digit after decimal point) and
 # `sep` (separator between the number and the prefix/unit).
 ax1.set_title('SI-prefix only ticklabels, 1-digit precision & ' +
-              'hair space separator')
-formatter1 = EngFormatter(places=1, sep=u"\u200a")  # U+200A is hair space
+              'thin space separator')
+formatter1 = EngFormatter(places=1, sep=u"\N{THIN SPACE}")  # U+2009
 ax1.xaxis.set_major_formatter(formatter1)
 ax1.plot(xs, ys)
 ax1.set_xlabel('Frequency [Hz]')

lib/matplotlib/ticker.py

@@ -1228,9 +1228,9 @@ def __init__(self, unit="", places=None, sep=" "):
             other useful options may be:
 
             * ``sep=""`` to append directly the prefix/unit to the value;
-            * ``sep="\\u2009"`` to use a thin space;
-            * ``sep="\\u202f"`` to use a narrow no-break space;
-            * ``sep="\\u00a0"`` to use a no-break space.
+            * ``sep="\\N{THIN SPACE}"`` (``U+2009``);
+            * ``sep="\\N{NARROW NO-BREAK SPACE}"`` (``U+202F``);
+            * ``sep="\\N{NO-BREAK SPACE}"`` (``U+00A0``).
         """
         self.unit = unit
         self.places = places