Notebook Viewer
Work with Jupyter notebooks — view, edit, execute cells, manage kernels, and navigate with full keyboard support.
Omnilib's Notebook Viewer lets you work with Jupyter notebooks (.ipynb files). View notebooks, edit cells, and execute code using real Python kernels with full keyboard navigation.
Overview
The Notebook Viewer provides:
- Cell display — View code and markdown cells
- Code execution — Run cells with Jupyter kernels
- Rich output — Display text, HTML, images, and errors
- Kernel management — Select kernels and conda environments
- Full keyboard navigation — Run, add, and convert cells without the mouse
- Tags — Apply tags per notebook from the ribbon
Getting Started
Opening a Notebook
Click any .ipynb file in the sidebar. The notebook opens showing all cells in order.
Understanding Cells
| Cell Type | Purpose |
|---|---|
| Code | Python code to execute |
| Markdown | Formatted text and documentation |
Viewing Notebooks
Code Cells
Code cells show:
- Source code — Syntax-highlighted Python
- Execution count —
[1],[2], etc. - Output — What the code produces
Markdown Cells
Markdown cells render headings, lists, tables, links, images, and mathematical formulas. Double-click to edit.
Executing Code
Keyboard Shortcuts for Execution
| Shortcut | Action |
|---|---|
Shift+Enter | Run cell and move to the next |
Cmd+Enter (Windows: Ctrl+Enter) | Run cell, stay on current |
Alt+Enter | Run cell and insert a new cell below |
Cmd+Shift+Enter (Windows: Ctrl+Shift+Enter) | Run all cells |
Running All Cells
Click Run All in the toolbar, or press Cmd+Shift+Enter (Windows: Ctrl+Shift+Enter).
Execution States
| State | Description |
|---|---|
| Idle | Kernel ready |
| Busy | Currently executing |
| Starting | Kernel is starting up |
| Dead | Kernel has stopped |
The kernel state indicator appears in the toolbar.
Cell Output
Text Output
Standard print output and text results display below the cell.
HTML Output
Rich HTML renders inline — DataFrames as formatted tables, interactive widgets, and custom HTML.
Images
Matplotlib figures, PIL images, and SVG graphics render directly in the notebook.
Errors
Error messages display with the error type, message, and full traceback with line numbers.
Editing Cells
Adding Cells
| Shortcut | Action |
|---|---|
Cmd+Shift+A (Windows: Ctrl+Shift+A) | Add cell above current |
Cmd+Shift+B (Windows: Ctrl+Shift+B) | Add cell below current |
Or click Add Cell in the toolbar and select Code or Markdown.
Converting Cell Types
With a cell selected (not in edit mode):
| Key | Action |
|---|---|
M | Convert to Markdown cell |
Y | Convert to Code cell |
Moving Cells
Select a cell and use Cmd+Shift+Up (Windows: Ctrl+Shift+Up) or Cmd+Shift+Down (Windows: Ctrl+Shift+Down) to reorder.
Deleting Cells
Select a cell and press Delete.
Full Keyboard Navigation
The notebook uses a two-mode system: Command mode (cell selected, not editing) and Edit mode (cursor inside a cell).
Press Escape to enter command mode. Press Enter to enter edit mode on the selected cell.
Command Mode Shortcuts
| Shortcut | Action |
|---|---|
Shift+Enter | Run cell and move to next |
Cmd+Enter | Run cell, stay |
Alt+Enter | Run cell and insert below |
Cmd+Shift+Enter | Run all cells |
Cmd+Shift+A | Add cell above |
Cmd+Shift+B | Add cell below |
M | Convert to Markdown |
Y | Convert to Code |
Delete | Delete cell |
Cmd+Shift+Up | Move cell up |
Cmd+Shift+Down | Move cell down |
Tags
Click the Tags button in the notebook toolbar ribbon to manage tags for the current notebook. Tags are stored in the notebook metadata and can be used to categorize notebooks across a project.
Kernel Management
Selecting a Kernel
Click the kernel selector in the toolbar:
System Kernels — Python kernels installed on your system, detected automatically.
Conda Environments — Environments from Conda or Miniconda. If the environment does not have ipykernel installed, Omnilib prompts you to install it with one click.
Conda Environment Selection
Select a conda environment from the kernel dropdown. Omnilib detects environments from your standard conda installation paths. If ipykernel is not installed in the selected environment, a prompt appears:
- Click Install ipykernel.
- Wait for installation to complete.
- The environment becomes available as a kernel.
Kernel Actions
| Action | Description |
|---|---|
| Restart | Stop and restart the kernel |
| Interrupt | Stop current execution |
| Shutdown | Stop the kernel completely |
Toolbar Actions
| Button | Action |
|---|---|
| Run All | Execute all cells |
| Interrupt | Stop current execution |
| Restart | Restart the kernel |
| Clear All Outputs | Remove all cell outputs |
| Save | Save the notebook |
| Tags | Open the tags ribbon |
Working with Data
import pandas as pd
df = pd.read_csv("data.csv")
df.head() # Displays as a formatted table
import matplotlib.pyplot as plt
plt.plot([1, 2, 3, 4])
plt.ylabel('Values')
plt.show() # Displays inline
Desktop-Only Features
Full kernel execution requires the Omnilib desktop app. The web version can view notebooks (read-only) and see existing outputs, but cannot execute code or start kernels.
Troubleshooting
Kernel Not Starting
- Ensure Python and Jupyter are installed.
- Check that the selected kernel is valid.
- Try restarting Omnilib.
Execution Stuck
- Click Interrupt to stop.
- If unresponsive, restart the kernel.
Missing Packages
- Open a terminal.
- Activate the relevant environment.
- Run
pip install package-name. - Restart the kernel.
Output Not Showing
- Check that the cell ran (look for an execution count).
- Ensure the code produces output.
- Try running the cell again.