float

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

coerce