DOC/Gallery example "Plotting a surface": Migrate frame settings to the new Frame/Axis syntax; part 2 (#4504)

Author: yvonnefroehlich

examples/gallery/3d_plots/grdview_surface.py

@@ -5,12 +5,10 @@
 The :meth:`pygmt.Figure.grdview()` method can plot 3-D surfaces with
 ``surftype="surface"``. Here, we supply the data as an :class:`xarray.DataArray` with
 the coordinate vectors ``x`` and ``y`` defined. Note that the ``perspective`` parameter
-here controls the azimuth and elevation angle of the view. We provide a list of two
-arguments to ``frame`` - the first argument specifies the :math:`x`- and :math:`y`-axes
-frame attributes and the second argument, prepended with ``"z"``, specifies the
-:math:`z`-axis frame attributes. Specifying the same scale for the ``projection`` and
-``zscale`` parameters ensures equal axis scaling. The ``shading`` parameter specifies
-illumination; here we choose an azimuth of 45° with ``shading="+a45"``.
+here controls the azimuth and elevation angle of the view. Specifying the same scale
+for the ``projection`` and ``zscale`` parameters ensures equal axis scaling. The
+``shading`` parameter specifies illumination; here we choose an azimuth of 45° with
+``shading="+a45"``.
 """
 
 # %%
@@ -48,7 +46,7 @@ def ackley(x, y):
     data,
     # Set annotations and gridlines in steps of five, and tick marks in steps of one
     frame=Frame(
-        axis=Axis(annot=5, tick=1, grid=5),
+        axis=Axis(annot=5, tick=1, grid=5),  # x and y axes
         zaxis=Axis(annot=5, tick=1, grid=5),
     ),
     projection=f"x{SCALE}c",