Float

From Computer Science Wiki
Programming basics[1]

A float represents real numbers and is written with a decimal point dividing the integer and fractional parts. [2]


Signed and unsigned[edit]

There is a deeper conversation about signed and unsigned numbers. You should know this:

  • A signed number can be positive or negative
  • An unsigned number can only be positive

A sign is basically an extra bit added to the binary number indicating it is negative or positive. There is more to this, but that is what you should know.

Difference between an int and a float[edit]

Integers and floats are two different kinds of numerical data. An integer (more commonly called an int) is a number without a decimal point. A float is a floating-point number, which means it is a number that has a decimal place. Floats are used when more precision is needed.[3]

Example[edit]

In PHP: You will remember PHP isn't a strictly typed language (although it can be set to be).

<?php
$a = 1234.65; // decimal number
$a = -1234.54; // a negative number
?>

In Python:

# decimal number:
a = 1234.65
# a negative number:
a = -1234.65

In Javascript:

// decimal number:
var a = 1234.65; 
// a negative number:
var a = -1234.65;

Standards[edit]

  • Define the terms: variable, constant, operator, object.

References[edit]