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class · Ruby 3.1

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
Comparing
Converting

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.