DOC/Gallery example "3-D scatter plots": Migrate frame settings to the new Frame/Axis syntax (#4502)

Author: Chuan1937

examples/gallery/3d_plots/scatter3d.py

@@ -9,14 +9,16 @@
 parameter has to include the :math:`x`, :math:`y`, :math:`z` axis limits in the
 form of (xmin, xmax, ymin, ymax, zmin, zmax), which can be done automatically
 using :func:`pygmt.info`. To plot the z-axis frame, set ``frame`` as a
-minimum to something like ``frame=["WsNeZ", "zaf"]``. Use ``perspective`` to
+minimum to something like ``Frame(axes="WsNeZ", zaxis=Axis(annot=True, tick=True))``.
+Use ``perspective`` to
 control the azimuth and elevation angle of the view, and ``zscale`` to adjust
 the vertical exaggeration factor.
 """
 
 # %%
 import pandas as pd
 import pygmt
+from pygmt.params import Axis, Frame
 
 # Load sample iris data
 df = pd.read_csv("https://github.com/mwaskom/seaborn-data/raw/master/iris.csv")
@@ -80,12 +82,13 @@
     # Set map dimensions (xmin, xmax, ymin, ymax, zmin, zmax)
     region=region,
     # Set frame parameters
-    frame=[
-        "WsNeZ3+tIris flower data set",  # z axis label positioned on 3rd corner, add title
-        "xafg+lPetal Width (cm)",
-        "yafg+lSepal Length (cm)",
-        "zafg+lPetal Length (cm)",
-    ],
+    frame=Frame(
+        axes="WsNeZ3",  # z axis label positioned on 3rd corner
+        title="Iris flower data set",
+        xaxis=Axis(annot=True, tick=True, grid=True, label="Petal Width (cm)"),
+        yaxis=Axis(annot=True, tick=True, grid=True, label="Sepal Length (cm)"),
+        zaxis=Axis(annot=True, tick=True, grid=True, label="Petal Length (cm)"),
+    ),
     # Set perspective to azimuth NorthWest (315°), at elevation 25°
     perspective=[315, 25],
     # Vertical exaggeration factor