update getting started: run python api and cli (isl-org#4754)

* update getting started insturctions

* Merge branch 'master' into yixing/update-getting-started

* update readme for print version number

README.md

@@ -48,12 +48,20 @@ Pre-built pip and conda packages support Ubuntu 18.04+, macOS 10.15+ and
 Windows 10 (64-bit) with Python 3.6-3.9.
 
 ```bash
-# Install Open3D stable release with pip (including in conda virtual environments)
-$ pip install open3d
+# Install
+pip install open3d
 
-# Test the installation
-$ python -c "import open3d as o3d; print(o3d)"
+# Verify installation
+python -c "import open3d as o3d; print(o3d.__version__)"
 
+# Python API
+python -c "import open3d as o3d; \
+           mesh = o3d.geometry.TriangleMesh.create_sphere(); \
+           mesh.compute_vertex_normals(); \
+           o3d.visualization.draw(mesh, raw_mode=True)"
+
+# Open3D CLI
+open3d example visualization/draw
 ```
 
 To get the latest features in Open3D, install the

docs/getting_started.in.rst

@@ -104,13 +104,21 @@ to install the latest development version on Linux for Python 3.9:
 Try it
 ------
 
-Now, try importing Open3D.
-
 .. code-block:: bash
 
-    python -c "import open3d as o3d"
+    # Verify installation
+    python -c "import open3d as o3d; print(o3d.__version__)"
+
+    # Python API
+    python -c "import open3d as o3d; \
+               mesh = o3d.geometry.TriangleMesh.create_sphere(); \
+               mesh.compute_vertex_normals(); \
+               o3d.visualization.draw(mesh, raw_mode=True)"
+
+    # Open3D CLI
+    open3d example visualization/draw
 
-If this works, congratulations, now Open3D has been successfully installed!
+If everything works, congratulations, now Open3D has been successfully installed!
 
 
 Troubleshooting: