# log2

This function basically asks "how many 2's do you need to multiply to get n?". A common example of use in programming would be to calculate the number of bits that are needed to represent a number. To do this we calculate the `log2(x)` of the number, round it down and add 1 - for example `log2(100)` returns 6.643856, which rounded down is 6, to which we add one and it gives us 7. So we need 7 bits to represent 100. It can also be used for describing exponential growth or
decay, and is often called a *binary logarithm*.

#### Syntax:

log2(n);

Argument |
Description |

n |
The input value. |

#### Returns:

Real

#### Example:

colourbits = floor(log2(colour)) - 1;

The above code stores the number of bits needed to represent the value stored in the variable "colour".