Python in Jupyter: Difference between revisions

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We are going to practice writing and running Python programs (often called "scripts").
We are going to practice writing and running Python programs (often called "scripts").


===Start your text editor===
=== Download a Jupyter Notebook ===  


# Launch the Visual Studio Code text editor. See the [[Windows_text_editor|Windows text editor setup]] instructions for the steps to do this.
Save the file CDSW_Jupyter_test_notebook.ipynb from the following link to your desktop: [https://communitydata.science/~groceryheist/CDSW_Jupyter_test_notebook.ipynb CDSW Jupter test notebook]
# Start a new, blank text file.
(To save, (on Windows) right click the link and choose "save link as..." On a Mac, Option + click will do the same).    If you're using a new Mac, it may change the name of your file from ending in .ipynb to ending in .txt. This will not work: use command-i (get info) and then click on the type section. Remove the .txt at the end of the file name and hit tab -- when your Mac asks you if you want to do this, say yes.
Save it as a .ipynb file (rename it if you forget).
Make sure you save it on the CDSW folder you've created on your desktop. (Or drag it into that folder).


===Write and save a short Python script===
=== Open the Notebook in Jupyter Web Browser ===  


# Add the following line to your new text file:
Start Jupyter as you were instructed to in a previous step.
In the Jupyter tab in your browser, navigate to your desktop in the list of folders and click on <code>CDSW_Jupyter_test_notebook.ipynb</code>.


<pre>
print("Hello World!")
</pre>


# Save the script as <code>hello.py</code> in your Desktop directory. The <code>.py</code> extension indicates that this file contains Python code.
=== Test the notebook ===


===Run the script===
Following the instructions in the notebook, run the cell (by clicking the "run" button in the tool bar or press "ENTER + SHIFT") that says:
  print("hello world")


# Start a new terminal prompt. See the [[Windows terminal navigation|terminal navigation on Windows]] instructions for the steps to do this. Recall that a terminal prompt will look like <code>C:\</code> and a Python prompt will look like <code>>>></code>. Make sure you are at a terminal prompt and not a Python prompt; if you are at a Python prompt, you can type <code>exit()</code> on a line by itself and then press enter to exit Python and return to a terminal prompt.
You should see "hello world" output right below. If that works you have a working setup for Python and Jupyter. If that doesn't work, you should ask for assistance!
# Navigate to your Desktop directory from a PowerShell terminal prompt, using the <code>ls</code> and <code>cd</code> commands. See the [[Windows terminal navigation|terminal navigation on Windows]] instructions for a refresher on using these commands. Don't hesitate to get help from a mentor on this step if you need it -- it's a new way of navigating around your computer, so it may be unintuitive at first!
# Once you are in your Desktop directory, you'll see <code>hello.py</code> in the output of <code>ls</code>.
# Type


<pre>
Feel free to play around in the notebook. Try it out and explore!
python hello.py
</pre>


and press enter. Doing this will cause Python to execute the contents of that script -- it should print "Hello World!" to the screen. What you've done here is run the Python application with an argument -- the name of a file, in this case "hello.py". Python knows that when you give it a file name as an argument, it should execute the contents of the provided file. You get the same result as if you typed
P.S. Feel free to try out Python commands in this notebook. It's for you to play with!


<pre>
print("Hello World!")
</pre>


at a Python prompt and press enter.
=== Success! You have a working Python and Jupyter setup! ===
 
===Success===
 
You created and ran your first Python script!
 
* When you run the <code>python</code> command by itself, you start a Python prompt. You can execute Python code interactively at that prompt.
* When you run the <code>python</code> command with a file name as an argument, Python executes the Python code in that file.


[[File:Champagne.png|100px]][[File:Party.png|125px]]
[[File:Champagne.png|100px]][[File:Party.png|125px]]
 
[[Category:CDSW]][[Category:Shared Pages]]
[[Category:CDSW]]

Revision as of 04:24, 18 January 2020

We are going to practice writing and running Python programs (often called "scripts").

Download a Jupyter Notebook

Save the file CDSW_Jupyter_test_notebook.ipynb from the following link to your desktop: CDSW Jupter test notebook (To save, (on Windows) right click the link and choose "save link as..." On a Mac, Option + click will do the same). If you're using a new Mac, it may change the name of your file from ending in .ipynb to ending in .txt. This will not work: use command-i (get info) and then click on the type section. Remove the .txt at the end of the file name and hit tab -- when your Mac asks you if you want to do this, say yes. Save it as a .ipynb file (rename it if you forget). Make sure you save it on the CDSW folder you've created on your desktop. (Or drag it into that folder).

Open the Notebook in Jupyter Web Browser

Start Jupyter as you were instructed to in a previous step. In the Jupyter tab in your browser, navigate to your desktop in the list of folders and click on CDSW_Jupyter_test_notebook.ipynb.


Test the notebook

Following the instructions in the notebook, run the cell (by clicking the "run" button in the tool bar or press "ENTER + SHIFT") that says:

 print("hello world")

You should see "hello world" output right below. If that works you have a working setup for Python and Jupyter. If that doesn't work, you should ask for assistance!

Feel free to play around in the notebook. Try it out and explore!

P.S. Feel free to try out Python commands in this notebook. It's for you to play with!


Success! You have a working Python and Jupyter setup!

Champagne.pngParty.png