A signed floating-point number.

Input Format:

A sequence of numeric digits, possibly prefixed with a sign character.

Use with do-loops:

When a Double variable is used as the dependent variable of a do-loop, the associated loop increment is also an Double.

Examples:

 print $Double(-2.3e-6)
 -> -2.3e-6

Context:

This datatype is mainly used to specify do-loop increments when the loop variable is a floating point datatype.