PHP for the Web: Visual QuickStart Guide, Fifth Edition

4. Using Numbers

In This Chapter

Creating the Form

Performing Arithmetic

Formatting Numbers

Understanding Precedence

Incrementing and Decrementing a Number

Creating Random Numbers

Review and Pursue

Chapter 2, “Variables,” briefly discussed the various types of variables, how to assign values to them, and how they’re generally used. In this chapter, you’ll work specifically with number variables—both integers (whole numbers) and floating-point numbers (aka floats or decimals).

You’ll begin by creating an HTML form that will be used to generate number variables. Then you’ll learn how to perform basic arithmetic, how to format numbers, and how to cope with operator precedence. The last two sections of this chapter cover incrementing and decrementing ...