Float

Introduction

A float is a decimal stored as binary in memory. We use scientific notation to represent the decimal. Scientific notation is a decimal number < 10 times some exponent of 10. For example: 8.23 * 10⁴ is in scientific notation. Decimals can be stored in 32 bits or 64 bits.

In a 32bit float, we have 1 bit for the sign (positive or negative), 23 bits for the significant figures (7 digits) and 8 bits for the exponent.

In a 64bit double we have 1 bit for the sign (positive or negative), 52 bits for the significant figures (16 digits) and 11 bits for the exponent.

Example

double x = 1.0/4.0;
double y = 1.78e5;
double z = -10.535246;