mirror of
https://github.com/ruby/ruby.git
synced 2022-11-09 12:17:21 -05:00
* string.c (scan_once): wrong condition to use mbclen2().
[ruby-dev:27535] * time.c (time_sunday): added predicate methods for the days of the week. [ruby-list:41340] git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@9472 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
matz
parent
563742204d
commit
c6b9f16231
8 changed files with 591 additions and 79 deletions
295
lib/rational.rb
295
lib/rational.rb
|
|
@ -1,41 +1,32 @@
|
|||
#
|
||||
# rational.rb -
|
||||
# $Release Version: 0.5 $
|
||||
# $Revision: 1.7 $
|
||||
# $Date: 1999/08/24 12:49:28 $
|
||||
# by Keiju ISHITSUKA(SHL Japan Inc.)
|
||||
# rational.rb -
|
||||
# $Release Version: 0.5 $
|
||||
# $Revision: 1.7 $
|
||||
# $Date: 1999/08/24 12:49:28 $
|
||||
# by Keiju ISHITSUKA(SHL Japan Inc.)
|
||||
#
|
||||
# --
|
||||
# Usage:
|
||||
# class Rational < Numeric
|
||||
# (include Comparable)
|
||||
# Documentation by Kevin Jackson and Gavin Sinclair.
|
||||
#
|
||||
# When you <tt>require 'rational'</tt>, all interactions between numbers
|
||||
# potentially return a rational result. For example:
|
||||
#
|
||||
# Rational(a, b) --> a/b
|
||||
#
|
||||
# Rational::+
|
||||
# Rational::-
|
||||
# Rational::*
|
||||
# Rational::/
|
||||
# Rational::**
|
||||
# Rational::%
|
||||
# Rational::divmod
|
||||
# Rational::abs
|
||||
# Rational::<=>
|
||||
# Rational::to_i
|
||||
# Rational::to_f
|
||||
# Rational::to_s
|
||||
#
|
||||
# Integer::gcd
|
||||
# Integer::lcm
|
||||
# Integer::gcdlcm
|
||||
# Integer::to_r
|
||||
#
|
||||
# Fixnum::**
|
||||
# Fixnum::quo
|
||||
# Bignum::**
|
||||
# Bignum::quo
|
||||
# 1.quo(2) # -> 0.5
|
||||
# require 'rational'
|
||||
# 1.quo(2) # -> Rational(1,2)
|
||||
#
|
||||
# See Rational for full documentation.
|
||||
#
|
||||
|
||||
#
|
||||
# Creates a Rational number (i.e. a fraction). +a+ and +b+ should be Integers:
|
||||
#
|
||||
# Rational(1,3) # -> 1/3
|
||||
#
|
||||
# Note: trying to construct a Rational with floating point or real values
|
||||
# produces errors:
|
||||
#
|
||||
# Rational(1.1, 2.3) # -> NoMethodError
|
||||
#
|
||||
def Rational(a, b = 1)
|
||||
if a.kind_of?(Rational) && b == 1
|
||||
a
|
||||
|
|
@ -43,10 +34,39 @@ def Rational(a, b = 1)
|
|||
Rational.reduce(a, b)
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Rational implements a rational class for numbers.
|
||||
#
|
||||
# <em>A rational number is a number that can be expressed as a fraction p/q
|
||||
# where p and q are integers and q != 0. A rational number p/q is said to have
|
||||
# numerator p and denominator q. Numbers that are not rational are called
|
||||
# irrational numbers.</em> (http://mathworld.wolfram.com/RationalNumber.html)
|
||||
#
|
||||
# To create a Rational Number:
|
||||
# Rational(a,b) # -> a/b
|
||||
# Rational.new!(a,b) # -> a/b
|
||||
#
|
||||
# Examples:
|
||||
# Rational(5,6) # -> 5/6
|
||||
# Rational(5) # -> 5/1
|
||||
#
|
||||
# Rational numbers are reduced to their lowest terms:
|
||||
# Rational(6,10) # -> 3/5
|
||||
#
|
||||
# But not if you use the unusual method "new!":
|
||||
# Rational.new!(6,10) # -> 6/10
|
||||
#
|
||||
# Division by zero is obviously not allowed:
|
||||
# Rational(3,0) # -> ZeroDivisionError
|
||||
#
|
||||
class Rational < Numeric
|
||||
@RCS_ID='-$Id: rational.rb,v 1.7 1999/08/24 12:49:28 keiju Exp keiju $-'
|
||||
|
||||
#
|
||||
# Reduces the given numerator and denominator to their lowest terms. Use
|
||||
# Rational() instead.
|
||||
#
|
||||
def Rational.reduce(num, den = 1)
|
||||
raise ZeroDivisionError, "denominator is zero" if den == 0
|
||||
|
||||
|
|
@ -63,13 +83,21 @@ class Rational < Numeric
|
|||
new!(num, den)
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Implements the constructor. This method does not reduce to lowest terms or
|
||||
# check for division by zero. Therefore #Rational() should be preferred in
|
||||
# normal use.
|
||||
#
|
||||
def Rational.new!(num, den = 1)
|
||||
new(num, den)
|
||||
end
|
||||
|
||||
private_class_method :new
|
||||
|
||||
#
|
||||
# This method is actually private.
|
||||
#
|
||||
def initialize(num, den)
|
||||
if den < 0
|
||||
num = -num
|
||||
|
|
@ -83,7 +111,15 @@ class Rational < Numeric
|
|||
@denominator = den.to_i
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns the addition of this value and +a+.
|
||||
#
|
||||
# Examples:
|
||||
# r = Rational(3,4) # -> Rational(3,4)
|
||||
# r + 1 # -> Rational(7,4)
|
||||
# r + 0.5 # -> 1.25
|
||||
#
|
||||
def + (a)
|
||||
if a.kind_of?(Rational)
|
||||
num = @numerator * a.denominator
|
||||
|
|
@ -98,7 +134,16 @@ class Rational < Numeric
|
|||
x + y
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns the difference of this value and +a+.
|
||||
# subtracted.
|
||||
#
|
||||
# Examples:
|
||||
# r = Rational(3,4) # -> Rational(3,4)
|
||||
# r - 1 # -> Rational(-1,4)
|
||||
# r - 0.5 # -> 0.25
|
||||
#
|
||||
def - (a)
|
||||
if a.kind_of?(Rational)
|
||||
num = @numerator * a.denominator
|
||||
|
|
@ -113,7 +158,17 @@ class Rational < Numeric
|
|||
x - y
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns the product of this value and +a+.
|
||||
#
|
||||
# Examples:
|
||||
# r = Rational(3,4) # -> Rational(3,4)
|
||||
# r * 2 # -> Rational(3,2)
|
||||
# r * 4 # -> Rational(3,1)
|
||||
# r * 0.5 # -> 0.375
|
||||
# r * Rational(1,2) # -> Rational(3,8)
|
||||
#
|
||||
def * (a)
|
||||
if a.kind_of?(Rational)
|
||||
num = @numerator * a.numerator
|
||||
|
|
@ -128,7 +183,14 @@ class Rational < Numeric
|
|||
x * y
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns the quotient of this value and +a+.
|
||||
# r = Rational(3,4) # -> Rational(3,4)
|
||||
# r / 2 # -> Rational(3,8)
|
||||
# r / 2.0 # -> 0.375
|
||||
# r / Rational(1,2) # -> Rational(3,2)
|
||||
#
|
||||
def / (a)
|
||||
if a.kind_of?(Rational)
|
||||
num = @numerator * a.denominator
|
||||
|
|
@ -144,7 +206,16 @@ class Rational < Numeric
|
|||
x / y
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns this value raised to the given power.
|
||||
#
|
||||
# Examples:
|
||||
# r = Rational(3,4) # -> Rational(3,4)
|
||||
# r ** 2 # -> Rational(9,16)
|
||||
# r ** 2.0 # -> 0.5625
|
||||
# r ** Rational(1,2) # -> 0.866025403784439
|
||||
#
|
||||
def ** (other)
|
||||
if other.kind_of?(Rational)
|
||||
Float(self) ** other
|
||||
|
|
@ -167,17 +238,37 @@ class Rational < Numeric
|
|||
x ** y
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns the remainder when this value is divided by +other+.
|
||||
#
|
||||
# Examples:
|
||||
# r = Rational(7,4) # -> Rational(7,4)
|
||||
# r % Rational(1,2) # -> Rational(1,4)
|
||||
# r % 1 # -> Rational(3,4)
|
||||
# r % Rational(1,7) # -> Rational(1,28)
|
||||
# r % 0.26 # -> 0.19
|
||||
#
|
||||
def % (other)
|
||||
value = (self / other).to_i
|
||||
return self - other * value
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns the quotient _and_ remainder.
|
||||
#
|
||||
# Examples:
|
||||
# r = Rational(7,4) # -> Rational(7,4)
|
||||
# r.divmod Rational(1,2) # -> [3, Rational(1,4)]
|
||||
#
|
||||
def divmod(other)
|
||||
value = (self / other).to_i
|
||||
return value, self - other * value
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns the absolute value.
|
||||
#
|
||||
def abs
|
||||
if @numerator > 0
|
||||
Rational.new!(@numerator, @denominator)
|
||||
|
|
@ -186,6 +277,15 @@ class Rational < Numeric
|
|||
end
|
||||
end
|
||||
|
||||
#
|
||||
# Returns +true+ iff this value is numerically equal to +other+.
|
||||
#
|
||||
# But beware:
|
||||
# Rational(1,2) == Rational(4,8) # -> true
|
||||
# Rational(1,2) == Rational.new!(4,8) # -> false
|
||||
#
|
||||
# Don't use Rational.new!
|
||||
#
|
||||
def == (other)
|
||||
if other.kind_of?(Rational)
|
||||
@numerator == other.numerator and @denominator == other.denominator
|
||||
|
|
@ -198,6 +298,9 @@ class Rational < Numeric
|
|||
end
|
||||
end
|
||||
|
||||
#
|
||||
# Standard comparison operator.
|
||||
#
|
||||
def <=> (other)
|
||||
if other.kind_of?(Rational)
|
||||
num = @numerator * other.denominator
|
||||
|
|
@ -232,14 +335,35 @@ class Rational < Numeric
|
|||
end
|
||||
end
|
||||
|
||||
#
|
||||
# Converts the rational to an Integer. Not the _nearest_ integer, the
|
||||
# truncated integer. Study the following example carefully:
|
||||
# Rational(+7,4).to_i # -> 1
|
||||
# Rational(-7,4).to_i # -> -2
|
||||
# (-1.75).to_i # -> -1
|
||||
#
|
||||
# In other words:
|
||||
# Rational(-7,4) == -1.75 # -> true
|
||||
# Rational(-7,4).to_i == (-1.75).to_i # false
|
||||
#
|
||||
def to_i
|
||||
Integer(@numerator.div(@denominator))
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Converts the rational to a Float.
|
||||
#
|
||||
def to_f
|
||||
@numerator.to_f/@denominator.to_f
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns a string representation of the rational number.
|
||||
#
|
||||
# Example:
|
||||
# Rational(3,4).to_s # "3/4"
|
||||
# Rational(8).to_s # "8"
|
||||
#
|
||||
def to_s
|
||||
if @denominator == 1
|
||||
@numerator.to_s
|
||||
|
|
@ -247,38 +371,69 @@ class Rational < Numeric
|
|||
@numerator.to_s+"/"+@denominator.to_s
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns +self+.
|
||||
#
|
||||
def to_r
|
||||
self
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns a reconstructable string representation:
|
||||
#
|
||||
# Rational(5,8).inspect # -> "Rational(5, 8)"
|
||||
#
|
||||
def inspect
|
||||
sprintf("Rational(%s, %s)", @numerator.inspect, @denominator.inspect)
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns a hash code for the object.
|
||||
#
|
||||
def hash
|
||||
@numerator.hash ^ @denominator.hash
|
||||
end
|
||||
|
||||
|
||||
attr :numerator
|
||||
attr :denominator
|
||||
|
||||
|
||||
private :initialize
|
||||
end
|
||||
|
||||
class Integer
|
||||
#
|
||||
# In an integer, the value _is_ the numerator of its rational equivalent.
|
||||
# Therefore, this method returns +self+.
|
||||
#
|
||||
def numerator
|
||||
self
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# In an integer, the denominator is 1. Therefore, this method returns 1.
|
||||
#
|
||||
def denominator
|
||||
1
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns a Rational representation of this integer.
|
||||
#
|
||||
def to_r
|
||||
Rational(self, 1)
|
||||
end
|
||||
|
||||
|
||||
#
|
||||
# Returns the <em>greatest common denominator</em> of the two numbers (+self+
|
||||
# and +n+).
|
||||
#
|
||||
# Examples:
|
||||
# 72.gcd 168 # -> 24
|
||||
# 19.gcd 36 # -> 1
|
||||
#
|
||||
# The result is positive, no matter the sign of the arguments.
|
||||
#
|
||||
def gcd(n)
|
||||
m = self.abs
|
||||
n = n.abs
|
||||
|
|
@ -298,13 +453,13 @@ class Integer
|
|||
end
|
||||
m << b
|
||||
end
|
||||
|
||||
|
||||
def gcd2(int)
|
||||
a = self.abs
|
||||
b = int.abs
|
||||
|
||||
|
||||
a, b = b, a if a < b
|
||||
|
||||
|
||||
while b != 0
|
||||
void, a = a.divmod(b)
|
||||
a, b = b, a
|
||||
|
|
@ -312,6 +467,14 @@ class Integer
|
|||
return a
|
||||
end
|
||||
|
||||
#
|
||||
# Returns the <em>lowest common multiple</em> (LCM) of the two arguments
|
||||
# (+self+ and +other+).
|
||||
#
|
||||
# Examples:
|
||||
# 6.lcm 7 # -> 42
|
||||
# 6.lcm 9 # -> 18
|
||||
#
|
||||
def lcm(other)
|
||||
if self.zero? or other.zero?
|
||||
0
|
||||
|
|
@ -320,6 +483,14 @@ class Integer
|
|||
end
|
||||
end
|
||||
|
||||
#
|
||||
# Returns the GCD _and_ the LCM (see #gcd and #lcm) of the two arguments
|
||||
# (+self+ and +other+). This is more efficient than calculating them
|
||||
# separately.
|
||||
#
|
||||
# Example:
|
||||
# 6.gcdlcm 9 # -> [3, 18]
|
||||
#
|
||||
def gcdlcm(other)
|
||||
gcd = self.gcd(other)
|
||||
if self.zero? or other.zero?
|
||||
|
|
@ -332,11 +503,13 @@ end
|
|||
|
||||
class Fixnum
|
||||
undef quo
|
||||
# If Rational is defined, returns a Rational number instead of a Fixnum.
|
||||
def quo(other)
|
||||
Rational.new!(self,1) / other
|
||||
end
|
||||
alias rdiv quo
|
||||
|
||||
|
||||
# Returns a Rational number if the result is in fact rational (i.e. +other+ < 0).
|
||||
def rpower (other)
|
||||
if other >= 0
|
||||
self.power!(other)
|
||||
|
|
@ -346,7 +519,7 @@ class Fixnum
|
|||
end
|
||||
|
||||
unless defined? 1.power!
|
||||
alias power! **
|
||||
alias power! **
|
||||
alias ** rpower
|
||||
end
|
||||
end
|
||||
|
|
@ -357,11 +530,13 @@ class Bignum
|
|||
end
|
||||
|
||||
undef quo
|
||||
# If Rational is defined, returns a Rational number instead of a Bignum.
|
||||
def quo(other)
|
||||
Rational.new!(self,1) / other
|
||||
end
|
||||
alias rdiv quo
|
||||
|
||||
|
||||
# Returns a Rational number if the result is in fact rational (i.e. +other+ < 0).
|
||||
def rpower (other)
|
||||
if other >= 0
|
||||
self.power!(other)
|
||||
|
|
@ -369,7 +544,7 @@ class Bignum
|
|||
Rational.new!(self, 1)**other
|
||||
end
|
||||
end
|
||||
|
||||
|
||||
unless defined? Complex
|
||||
alias ** rpower
|
||||
end
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue