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class · Ruby 3.2

Float

< Numeric 48 instance methods

A Float object represents a sometimes-inexact real number using the native architecture’s double-precision floating point representation.

Floating point has a different arithmetic and is an inexact number. So you should know its esoteric system. See following:

You can create a Float object explicitly with:

A floating-point literal.

You can convert certain objects to Floats with:

Method Float.

What’s Here

First, what’s elsewhere. Class Float:

Inherits from class Numeric.

Here, class Float provides methods for:

Querying

finite?: Returns whether self is finite.
hash: Returns the integer hash code for self.
infinite?: Returns whether self is infinite.
nan?: Returns whether self is a NaN (not-a-number).

Comparing

<: Returns whether self is less than the given value.
<=: Returns whether self is less than or equal to the given value.
<=>: Returns a number indicating whether self is less than, equal to, or greater than the given value.
== (aliased as === and eql?): Returns whether self is equal to the given value.
>: Returns whether self is greater than the given value.
>=: Returns whether self is greater than or equal to the given value.

Converting

% (aliased as modulo): Returns self modulo the given value.
*: Returns the product of self and the given value.
**: Returns the value of self raised to the power of the given value.
+: Returns the sum of self and the given value.
-: Returns the difference of self and the given value.
/: Returns the quotient of self and the given value.
ceil: Returns the smallest number greater than or equal to self.
coerce: Returns a 2-element array containing the given value converted to a Float and self
divmod: Returns a 2-element array containing the quotient and remainder results of dividing self by the given value.
fdiv: Returns the Float result of dividing self by the given value.
floor: Returns the greatest number smaller than or equal to self.
next_float: Returns the next-larger representable Float.
prev_float: Returns the next-smaller representable Float.
quo: Returns the quotient from dividing self by the given value.
round: Returns self rounded to the nearest value, to a given precision.
to_i (aliased as to_int): Returns self truncated to an Integer.
to_s (aliased as inspect): Returns a string containing the place-value representation of self in the given radix.
truncate: Returns self truncated to a given precision.

Instance methods 48

#% #* #** #+ #- #-@ #/ #< #<= #<=> #== #=== #> #>= #abs #angle #arg #ceil #coerce #denominator #divmod #eql? #fdiv #finite? #floor #hash #infinite? #inspect #magnitude #modulo #nan? #negative? #next_float #numerator #phase #positive? #prev_float #quo #rationalize #round #to_d #to_f #to_i #to_int #to_r #to_s #truncate #zero?

Constants

DIG

The minimum number of significant decimal digits in a double-precision floating point.

Usually defaults to 15.

EPSILON

The difference between 1 and the smallest double-precision floating point number greater than 1.

Usually defaults to 2.2204460492503131e-16.

INFINITY

An expression representing positive infinity.

MANT_DIG

The number of base digits for the double data type.

Usually defaults to 53.

MAX

The largest possible integer in a double-precision floating point number.

Usually defaults to 1.7976931348623157e+308.

MAX_10_EXP

The largest positive exponent in a double-precision floating point where 10 raised to this power minus 1.

Usually defaults to 308.

MAX_EXP

The largest possible exponent value in a double-precision floating point.

Usually defaults to 1024.

MIN

The smallest positive normalized number in a double-precision floating point.

Usually defaults to 2.2250738585072014e-308.

If the platform supports denormalized numbers, there are numbers between zero and Float::MIN. 0.0.next_float returns the smallest positive floating point number including denormalized numbers.