A floating-point number (float) consists of a sequence of digits with
an embedded decimal point, optionally preceded by a minus sign (-),
and optionally followed by an exponent consisting of upper- or
lowercase `E`

and a signed base 10 integer. Examples of floats
are:

1.0 -23.45 187.6E12 -0.0234e15 12.0E-2

Note that there must be at least one digit before, and one digit after, the decimal point.