Jupyter Notebook Notes
Intro to Jupyter Notebook
Pythons Jupyter Notebook:
- Allows us to program in a web browser.
- Is a mix of code, instructions and output; all of this information is displayed 'in line' in one web page.
- It is used by Scientists and Researchers, and is very useful for writing code that 'tells a story'.
- Not useful for writing an application.
The files that Jupyter creates/opens are ipynb files (i python notebook file).
Kernal: A programming environment. Jupyter by default runs Python, but there are Jupyter Kernals for many other programming languages e.g. R, Java and Scala.
ie a Kernal is basically what programming language we want to use.
Examples of Notebooks can be found at:
This link may be useful to help us with the Modelling aspect.
The Jupyter Notebook Environment
If we click a box (cell) it turns green.
We are then in edit mode and can write the program.
In [*] means that the current cell is running.
In [x] where x is a number represents the execution order of the cells.
When the * becomes a number it finishes running.
Blue: Means we are in command mode.
Hit esc key on keyboard to go to command mode.
Command mode: press button to most right to get a list of commands.
Example of a Command: turn line numbers on. press Esc and then l when clicked on the cell.
If one cell is still running, and we edit a second cell and try to run it it won't work.
We have to either make the cell finish running or restart the Kernal to solve the problem- Press the restart Kernal button.
When finished with the Jupyter Notebook, go to file --> Close and Halt to quit app and terminate the Kernal
Note: If a cell later on uses a variable or class from a previous cell, we must run the previous cell before running this cell so that it is in memory.
Going on Cell ---> Cell Type ----> Markdown can allows us to add Markdown language into the code to the notebook - we can then explain any concepts that we need to in that cell.
% - the commands arguments will all come from that same line. (Line Magics)
%% - the entire cell will be used as that commands arguments. (Cell Magics)
e.g. %lsmagic is a magic command that will list all the Magic Commands.
More examples are in the youtube tutorials.
%pwd - magic command that will print working directory.
- Going to file---> Download as allows us to export the file in many different ways.
- e.g. HTML, can allow us to post in a blog...or something similar.
- The ipynb file is like a Json file- it contains all the info needed