In this Lesson we learn How To Read an External CSV File into a multi-dimensional Array in Python by making a Supermarket Price Checker Program.
We first learn about the Structure of CSV Files: Rows in the input file are Records, and the values separated by commas in each Row or Line are Fields.
We then find out how to make an Input CSV (Comma Separated Values) File using Windows Notepad (or any other basic Text Editor like the Free Download Notepad ++)
The Python Processing Flow that is needed for CSV Files needs to be understood as we progress through this Lesson.
We strongly suggest getting these Downloads as well as watching the Lesson Video.
The Lesson Downloads explain in detail how we do the Python Coding which is needed to Read a CSV File into a 2 Dimensional Array and apply filters to its contents in the Program.
The downloads also contain a Challenge Task to check and reinforce Student Learning.
If you are a Teacher or Instructor then click the DOWNLOADS link below and get the lesson materials for your students.
The Downloads are critically important if your school or institution blocks or discourages YouTube Videos.
The Lesson can be fully completed using the Download Guides without watching the Video.
Give the Overview and Step by Step Guide PDFs to your students and we think you will find that some of them will "get it" very quickly.
The other students will greatly benefit from watching the video for this lesson which goes through everything in full detail slowly with step by step with repetition of examples.
Or simply use the Downloads to do your own in class Presentation and Lesson on Reading CSV Files and Processing 2 Dimensional Arrays in Python.
Because we are a slow talker, make sure students use the YouTube Player Bar Tools Cog to set the speed to 1.5x or even 1.75x
Note that the example Lesson Images shown on this web page are basic Printscreens, whereas the actual original Images are of perfect clarity and quality in both the downloadable PDF Guide and Word Document for this lesson.
LESSON OVERVIEW
This lesson consists of a Video Presentation and Written Instructions where we cover the following:
- Introduction and Preview of Finished Program
- Overview of CSV Files and Python Processing
- Structure of a CSV File
- Creating and Editing CSV Files using Windows Notepad
- Adding and Deleting CSV File Data using Notepad
- Python 2D Array Structure for Storing CSV Records
- Python CSV File 2D Array Processing Summary
- Overview of Quote of the Day Challenge Task
- V1-Setting up a Loop for Repeated Price Check Requests
- V2-Load Input CSV File Records into a 2D Array
- V3-User Selects Category for Price Check
- V4-Process User Selection and Print Price List
- V5-Price Check Using Separate Category Arrays
- Challenge Task - Random Quote of the Day
- Our Website Python Programming Course
- Video Wrap Up and Outro
Watch the following YouTube Video Tutorial about CSV Files and 2D Arrays.
USE THE YOU TUBE PLAYER TOOLS COG TO WATCH THE VIDEO AT 1.5X OR EVEN 1.75X SPEED.
We highly recommend you use the RESOURCE MATERIALS available below
to follow along step by step with the Tutorial Video.
The YouTube Video is free to watch as many times as you want, and the Lesson Build Guide including all required Images and full program code listing(s) are available at a small cost which can be paid for and downloaded using PayPal.
Before purchasing and downloading the following resources, check first with your Teacher or Instructor, as they may already have copies of these documents to give to you.
Our Programming Learning Modules are designed for complete beginners, and they have been extensively trialled with High School students learning Programming for the first time. They have a proven track record of being able to get everyone up and running with Python - the world's most popular Beginner Programmer's language.
We highly recommend using the Step by Step Summary Guide as well as the other support materials to maximise learning outcomes.
Our students have found the Summary Guide to be far more useful than re-watching the Video, when it comes time for them to apply their newly acquired skills to Application Build tasks.
Prices for the Resource Package including the Guide, Images, Form Design, and full Program Code Listings are:
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