Export axis direction correctly (fixes #301 and fixes #302)

Author: Lukas Müller

test/test_fancy_colorbar_reference.tex

@@ -11,6 +11,7 @@
 x grid style={white!69.01960784313725!black},
 xmin=-0.5, xmax=2.5,
 xtick style={color=black},
+y dir=reverse,
 y grid style={white!69.01960784313725!black},
 ymin=-0.5, ymax=2.5,
 ytick style={color=black}

test/test_noise2_reference.tex

@@ -12,6 +12,7 @@
 x grid style={white!69.01960784313725!black},
 xmin=-0.5, xmax=249.5,
 xtick style={color=black},
+y dir=reverse,
 y grid style={white!69.01960784313725!black},
 ymin=-0.5, ymax=249.5,
 ytick style={color=black}

test/test_noise_reference.tex

@@ -12,6 +12,7 @@
 x grid style={white!69.01960784313725!black},
 xmin=-0.5, xmax=249.5,
 xtick style={color=black},
+y dir=reverse,
 y grid style={white!69.01960784313725!black},
 ymin=-0.5, ymax=249.5,
 ytick style={color=black}

tikzplotlib/axes.py

@@ -59,12 +59,17 @@ def __init__(self, data, obj):
                 )
 
         # Axes limits.
-        # Sort the limits so make sure that the smaller of the two is actually *min.
         ff = data["float format"]
-        xlim = sorted(list(obj.get_xlim()))
-        self.axis_options.append(("xmin=" + ff + ", xmax=" + ff).format(*xlim))
-        ylim = sorted(list(obj.get_ylim()))
-        self.axis_options.append(("ymin=" + ff + ", ymax=" + ff).format(*ylim))
+        xlim = list(obj.get_xlim())
+        ylim = list(obj.get_ylim())
+        # Sort the limits so make sure that the smaller of the two is actually *min.
+        self.axis_options.append(("xmin=" + ff + ", xmax=" + ff).format(*sorted(xlim)))
+        self.axis_options.append(("ymin=" + ff + ", ymax=" + ff).format(*sorted(ylim)))
+        # When the axis is inverted add additional option
+        if (xlim != sorted(xlim)):
+            self.axis_options.append("x dir=reverse")
+        if (ylim != sorted(ylim)):
+            self.axis_options.append("y dir=reverse")
 
         # axes scaling
         if obj.get_xscale() == "log":