I’ve got problems using matplotlib in Panel - somehow plots are visible in Jupyter notebook, but when doing ‘Preview with Panel’ no plot is show: the pane where the plot should be is empty.
Therefore I have tried to run examples from the Panel documentation, namely from Component Gallery
I have downloaded the notebook from https://raw.githubusercontent.com/holoviz/panel/main/examples/reference/panes/Matplotlib.ipynb and ran all cells. Everything but the example in “Using the interactive Matplotlib backend” section shows correctly in the notebook interface, however when I try ‘Preview with Panel’, or run panel serve Matplotlib.ipynb --dev from the terminal (in JupyterLab) I get the following strange error:
2024-10-15 11:11:00,499 Uncaught exception GET /00-panel-Matplotlib (172.18.56.66)
HTTPServerRequest(protocol='http', host='158.75.112.151:5006', method='GET', uri='/Matplotlib', version='HTTP/1.1', remote_ip='172.18.56.66')
Traceback (most recent call last):
File ".venv/lib/python3.12/site-packages/tornado/web.py", line 1790, in _execute
result = await result
^^^^^^^^^^^^
File ".venv/lib/python3.12/site-packages/panel/io/server.py", line 466, in get
session = await self.get_session()
^^^^^^^^^^^^^^^^^^^^^^^^
File ".venv/lib/python3.12/site-packages/panel/io/server.py", line 356, in get_session
session = await super().get_session()
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".venv/lib/python3.12/site-packages/bokeh/server/views/session_handler.py", line 145, in get_session
session = await self.application_context.create_session_if_needed(session_id, self.request, token)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File ".venv/lib/python3.12/site-packages/bokeh/server/contexts.py", line 240, in create_session_if_needed
self._application.initialize_document(doc)
File ".venv/lib/python3.12/site-packages/panel/io/application.py", line 149, in initialize_document
super().initialize_document(doc)
File ".venv/lib/python3.12/site-packages/bokeh/application/application.py", line 190, in initialize_document
h.modify_document(doc)
File ".venv/lib/python3.12/site-packages/panel/io/handlers.py", line 668, in modify_document
nodes = ast.parse(source, os.fspath(path))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/ast.py", line 52, in parse
return compile(source, filename, mode, flags,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "notebooks/panel/Matplotlib.ipynb", line 190
" for (const name in js_exports) {\n",
SyntaxError: invalid syntax
When I examine the file, it turns out that this line comes from the very first cell, with the following code:
import panel as pn
pn.extension('ipywidgets')
When I look at the Matplotlib.ipynb file with less -N, this is what I see:
53 {
54 "data": {
55 "application/javascript": [
56 "(function(root) {\n",
57 " function now() {\n",
58 " return new Date();\n",
59 " }\n",
60 "\n",
[...]
188 " document.head.appendChild(element);\n",
189 " }\n",
190 " for (const name in js_exports) {\n",
191 " const url = js_exports[name];\n",
192 " const escaped = encodeURI(url)\n",
Could you help me debug this problem?
List of relevant packages installed:
- bokeh==3.6.0
- holoviews==1.19.1
- hvplot==0.11.0
- ipykernel==6.29.5
- ipympl==0.9.4
- ipython==8.27.0
- ipython-genutils==0.2.0
- ipywidgets==8.1.5
- ipywidgets_bokeh==1.6.0
- jupyter-events==0.10.0
- jupyter-lsp==2.2.5
- jupyter-server-mathjax==0.2.6
- jupyter_client==8.6.3
- jupyter_core==5.7.2
- jupyter_server==2.14.2
- jupyter_server_terminals==0.5.3
- jupyterlab==4.2.5
- jupyterlab_pygments==0.3.0
- jupyterlab_server==2.27.3
- jupyterlab_widgets==3.0.13
- matplotlib==3.9.2
- matplotlib-inline==0.1.7
- panel==1.5.2
- pyviz_comms==3.0.3
- watchfiles==0.24.0