Computing with Numbers

Name: Computing with Numbers
Author: John Crabtree

Learn common numeric types and the techniques for converting values and strings to numbers

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Course: On-Demand

Computer programmers use variables to keep track of information. This is done by using the assignment statement. Now syntactically, this process is largely the same in most languages. You have a variable on the left and the information on the right, but the proper way to think about what actually happens under the covers differ slightly depending on the language you're talking about. Now in some languages, like C, you should think of the variable as being a box into which you place a value. That is not the way you should think about Python. Instead, you should think of the variable as some kind of name that you are associating with an object because Python is an object-oriented language. So when you have a variable, you should think of it as being bound to some particular object. Now, in some Python books, you may read phrases like putting values into variables or variables holding values, and that's fine, but one of the best ways to think about this, just think about the variable as being some kind of label or sticky note, and when you're actually binding or sticking a label onto an object. Now be aware that this is not like algebra. In algebra, you can say X equal three or three equal X, and that means the same thing. That is not gonna work in programming. Because with programming, you always have to have the variable on the left and you can't have more than one variable. It's perfectly fine in algebra to say X plus Y equals seven, but the equal sign does not mean the same thing as it does in math. Like I mentioned, the equal sign means assignment. So when you say X equal three, you are binding the sticky to an object, an integer object with a value three, or you can apply a sticky note to the string object, hello. And you can change your mind. You can decide I don't want X to be labeling three, instead I want X to label the string bye. And you can change Y to be associated with a floating point number. Now also be aware that two variables can actually point to or label the same object in memory. So I can say X is going to be bound to two and Y is going to be bound to the same object. So the bottom line is keep in mind that in Python, when you do assignment, you are assigning a name or sticky note to some kind of object in memory.

Beginner Provider : John Crabtree 4 Lessons · 21m in Arabic, German, English, Spanish, French, Portuguese, Chinese

Course Description

These lessons begin with a discussion of the most commonly used numeric types: int and float. Techniques for converting values between numeric types are discussed along with a demonstration of converting strings to numbers. The evaluation of various arithmetic expressions is covered along with a practical example of the use of floor division in conjunction with the modulo operator.

LEARNING OBJECTIVES:

What You'll Learn

Distinguish between the two most commonly used numeric types, int and float
Convert values between numeric types using practical techniques
Convert strings to numbers
Evaluate arithmetic expressions
Apply floor division together with the modulo operation

Key Takeaways

The two most commonly used numeric types are int and float.
Values can be converted between numeric types, and strings can be converted to numbers.
Arithmetic expressions can be evaluated, including a practical example of floor division used with the modulo operator.
The course also addresses type conversion and rounding of numeric values.