parentheses in latex are off by default. added latex information to tutorial

robfalck · robfalck · commit 9baf3bc3f1a5 · 2011-05-11T07:17:30.000-04:00
diff --git a/quantities/__init__.py b/quantities/__init__.py
@@ -213,6 +213,27 @@
    >>> print pq.constants.proton_mass.simplified
    1.672621637e-27 kg
    +/-8.3e-35 kg (1 sigma)
+   
+A Latex representation of the dimensionality may be obtained in the following fashion::
+
+    >>> g = pq.Quantity(9.80665,'m/s**2')
+    >>> mass = 50 * pq.kg
+    >>> weight = mass*g
+    >>> print weight.dimensionality.latex
+    $\mathrm{\frac{kg{\cdot}m}{s^{2}}}$
+    >>> weight.units = pq.N
+    >>> print weight.dimensionality.latex
+    $\mathrm{N}$
+
+The Latex output is compliant with the MathText subset used by Matplotlib.  To add 
+formatted units to the axis label of a Matplotlib figure, one could use::
+
+    >>> ax.set_ylabel('Weight ' + weight.dimensionality.latex)
+    
+Greater customization is available via the markup.format_units_latex function.  It allows 
+the user to modify the font, the multiplication symbol, or to encapsulate the latex
+string in parentheses.  Due to the complexity of CompoundUnits, the latex rendering
+of CompoundUnits will utilize the latex \frac{num}{den} construct.
 
 Although it is not illustrated in this guide, unicode symbols can be
 used to provide a more compact representation of the units. This
diff --git a/quantities/markup.py b/quantities/markup.py
@@ -87,7 +87,7 @@ def format_units_unicode(udict):
     return res
 
 
-def format_units_latex(udict,font='mathrm',mult=r'\cdot',paren=True):
+def format_units_latex(udict,font='mathrm',mult=r'\cdot',paren=False):
     '''
     Replace the units string provided with an equivalent latex string.
     
@@ -100,8 +100,8 @@ def format_units_latex(udict,font='mathrm',mult=r'\cdot',paren=True):
     'mathit', 'mathsf', and 'mathtt'.
     
     Multiplication (*) are replaced with the symbol specified by the mult argument.
-    By default this is a blank string (no multiplication symbol).  Other useful
-    options may be r'\cdot' or r'*'
+    By default this is the latex \cdot symbol.  Other useful
+    options may be '' or '*'.
     
     If paren=True, encapsulate the string in '\left(' and '\right)'
     
