do not output style line if no rotation specified

Author: satejsoman

matplotlib2tikz/axes.py

@@ -46,14 +46,14 @@ def __init__(self, data, obj):
         if xlabel:
             xlabel = mpl_backend_pgf.common_texification(xlabel)
             self.axis_options.append(u"xlabel={{{}}}".format(xlabel))
-            if xrotation != 0.0:
+            if xrotation != 90:
                 self.axis_options.append(u"xlabel style={{rotate={}}}".format(xrotation - 90))
         ylabel = obj.get_ylabel()
         yrotation = obj.yaxis.get_label().get_rotation()
         if ylabel:
             ylabel = mpl_backend_pgf.common_texification(ylabel)
             self.axis_options.append(u"ylabel={{{}}}".format(ylabel))
-            if yrotation != 0.0:
+            if yrotation != 90:
                 self.axis_options.append(u"ylabel style={{rotate={}}}".format(yrotation - 90))
 
         # Axes limits.