float
number &optional prototype => float
number—a real.
prototype—a float.
float—a float.
float converts a
real
number to a float.
If a prototype is supplied, a float is returned that is mathematically equal to number but has the same format as prototype.
If prototype is not supplied, then if the number is already a float, it is returned; otherwise, a float is returned that is mathematically equal to number but is a single float.
(float 0) => 0.0 (float 1 .5) => 1.0 (float 1.0) => 1.0 (float 1/2) => 0.5 => 1.0d0 OR=> 1.0 (eql (float 1.0 1.0d0) 1.0d0) => true