From 9f1fb76ff9d9f447292103dd0b62c2fa13e574b4 Mon Sep 17 00:00:00 2001
From: Arne Naegel <naegel@gcsc.uni-frankfurt.de>
Date: Fri, 14 Jun 2024 06:12:02 +0200
Subject: [PATCH] Protecting pyvista: static, trame,...

---
 .../tutorial-solver/example01-smoothers.ipynb | 24 ++++++++++++++-----
 .../tutorial-solver/example01-smoothers.py    | 17 +++++++++----
 2 files changed, 30 insertions(+), 11 deletions(-)

diff --git a/content/tutorial-solver/example01-smoothers.ipynb b/content/tutorial-solver/example01-smoothers.ipynb
index ad136da..09ce214 100644
--- a/content/tutorial-solver/example01-smoothers.ipynb
+++ b/content/tutorial-solver/example01-smoothers.ipynb
@@ -304,12 +304,24 @@
     }
    ],
    "source": [
-    "import pyvista\n",
-    "#pyvista.start_xvfb()\n",
-    "#pyvista.set_jupyter_backend('static')\n",
-    "pyvista.set_jupyter_backend('trame')\n",
-    "result = pyvista.read( \"Error_gs.vtu\")\n",
-    "result.plot(scalars=\"u\", show_edges=True, cmap='jet')"
+    "try:\n",
+    "    import pyvista\n",
+    "except ModuleNotFoundError:\n",
+    "    print(\"pyvista is required for this demo\")\n",
+    "    exit(0)\n",
+    "\n",
+    "try:  \n",
+    "    # Activate the following lines binder, colab etc.\n",
+    "    pyvista.start_xvfb()\n",
+    "    pyvista.set_jupyter_backend('static')\n",
+    "\n",
+    "    # Activate locally, if trame exists.\n",
+    "    # pyvista.set_jupyter_backend('trame')\n",
+    "    \n",
+    "    result = pyvista.read( \"Error_gs.vtu\")\n",
+    "    result.plot(scalars=\"u\", show_edges=True, cmap='jet')\n",
+    "except:\n",
+    "     print(\"Plotting failed.\")"
    ]
   },
   {
diff --git a/content/tutorial-solver/example01-smoothers.py b/content/tutorial-solver/example01-smoothers.py
index 990cad5..5eddccc 100644
--- a/content/tutorial-solver/example01-smoothers.py
+++ b/content/tutorial-solver/example01-smoothers.py
@@ -223,11 +223,18 @@ def PlotResults(history, title):
     print("pyvista is required for this demo")
     exit(0)
 
-#pyvista.start_xvfb()
-#pyvista.set_jupyter_backend('static')
-pyvista.set_jupyter_backend('trame')
-result = pyvista.read( "Error_gs.vtu")
-result.plot(scalars="u", show_edges=True, cmap='jet')
+try:  
+    # Activate the following lines binder, colab etc.
+    pyvista.start_xvfb()
+    pyvista.set_jupyter_backend('static')
+
+    # Activate locally, if trame exists.
+    # pyvista.set_jupyter_backend('trame')
+    
+    result = pyvista.read( "Error_gs.vtu")
+    result.plot(scalars="u", show_edges=True, cmap='jet')
+except:
+     print("Plotting failed.")
 
 
 # In[ ]: