Add support for Bezier paths with datetime x-axis

Author: harenbrs

tikzplotlib/_path.py

@@ -29,8 +29,6 @@ def draw_path(data, path, draw_options=None, simplify=None):
     xformat = "{}" if x_is_date else ff
     prev = None
     for vert, code in path.iter_segments(simplify=simplify):
-        if x_is_date:
-            vert = [num2date(vert[0]), vert[1]]
         # nschloe, Oct 2, 2015:
         #   The transform call yields warnings and it is unclear why. Perhaps
         #   the input data is not suitable? Anyhow, this should not happen.
@@ -43,8 +41,12 @@ def draw_path(data, path, draw_options=None, simplify=None):
         # if code == mpl.path.Path.STOP: pass
         is_area = False
         if code == mpl.path.Path.MOVETO:
+            if x_is_date:
+                vert = [num2date(vert[0]), vert[1]]
             nodes.append(("(axis cs:" + xformat + "," + ff + ")").format(*vert))
         elif code == mpl.path.Path.LINETO:
+            if x_is_date:
+                vert = [num2date(vert[0]), vert[1]]
             nodes.append(("--(axis cs:" + xformat + "," + ff + ")").format(*vert))
         elif code == mpl.path.Path.CURVE3:
             # Quadratic Bezier curves aren't natively supported in TikZ, but
@@ -68,41 +70,54 @@ def draw_path(data, path, draw_options=None, simplify=None):
             Q1 = 1.0 / 3.0 * prev + 2.0 / 3.0 * vert[0:2]
             Q2 = 2.0 / 3.0 * vert[0:2] + 1.0 / 3.0 * vert[2:4]
             Q3 = vert[2:4]
+            if x_is_date:
+                Q1 = [num2date(Q1[0]), Q1[1]]
+                Q2 = [num2date(Q2[0]), Q2[1]]
+                Q3 = [num2date(Q3[0]), Q3[1]]
             nodes.append(
                 (
                     ".. controls (axis cs:"
-                    + ff
+                    + xformat
                     + ","
                     + ff
                     + ") "
                     + "and (axis cs:"
-                    + ff
+                    + xformat
                     + ","
                     + ff
                     + ") "
                     + ".. (axis cs:"
-                    + ff
+                    + xformat
                     + ","
                     + ff
                     + ")"
                 ).format(Q1[0], Q1[1], Q2[0], Q2[1], Q3[0], Q3[1])
             )
         elif code == mpl.path.Path.CURVE4:
             # Cubic Bezier curves.
+            if x_is_date:
+                vert = [
+                    num2date(vert[0]),
+                    vert[1],
+                    num2date(vert[2]),
+                    vert[3],
+                    num2date(vert[4]),
+                    vert[5],
+                ]
             nodes.append(
                 (
                     ".. controls (axis cs:"
-                    + ff
+                    + xformat
                     + ","
                     + ff
                     + ") "
                     + "and (axis cs:"
-                    + ff
+                    + xformat
                     + ","
                     + ff
                     + ") "
                     + ".. (axis cs:"
-                    + ff
+                    + xformat
                     + ","
                     + ff
                     + ")"