Simple Python Calculator using a Dictionary and Functions for Operators

A look at how to, and why you should, use functions in your Python programs.

We enhance the quiz program by reading the questions and answers from a file. Source code

Let’s look at two very nice features of Tynker. The physics feature allows you to have falling objects and accurate projectile motion, combined with adjustments for gravity, friction, density, gravity, and much more. Cloning lets you have multiple instances of actors (like Scratch sprites), without having to duplicate code.

This lesson creates a simple calculator using a dictionary to look up functions for operators. The point is to practice more with dictionaries, and to learn about higher-order functions. Source code

Showing how to create multiple turtles in Kojo, and make them wander around. Uses Scala features map and foreach.

We show how to use Python's input function to get numbers, without the program breaking if something other than a number is entered.

We respond to a viewer question and add features to limit the number of questions displayed, and to display the questions that were answered wrong.

How to make special sound effects using the free audio program Audacity. A small correction: I said that a 13-semitone change would move the pitch an octave, but it is actually 12. There are 12 different notes, and to move an octave you move 12 times to get back to the same note of the scale.

Carter Sande teaches how to use functions to a class at Diablo Valley College College for Kids. A couple of notes on this excellent presentation: At one point Carter says “brackets” when he means parentheses. And for style, I prefer spaces around operators, and whitespace around functions.

We add a feature limiting the number of times an event can occur.