Returns true
if the named files are identical.
file_1 and file_2 can be an IO
object.
open("a", "w") {} p File.identical?("a", "a") #=> true p File.identical?("a", "./a") #=> true File.link("a", "b") p File.identical?("a", "b") #=> true File.symlink("a", "c") p File.identical?("a", "c") #=> true open("d", "w") {} p File.identical?("a", "d") #=> false
Returns a string which represents the encoding for programmers.
Encoding::UTF_8.inspect #=> "#<Encoding:UTF-8>" Encoding::ISO_2022_JP.inspect #=> "#<Encoding:ISO-2022-JP (dummy)>"
Creates a printable version of e.
Returns a string containing a human-readable representation of obj. The default inspect
shows the object’s class name, an encoding of its memory address, and a list of the instance variables and their values (by calling inspect
on each of them). User defined classes should override this method to provide a better representation of obj. When overriding this method, it should return a string whose encoding is compatible with the default external encoding.
[ 1, 2, 3..4, 'five' ].inspect #=> "[1, 2, 3..4, \"five\"]" Time.new.inspect #=> "2008-03-08 19:43:39 +0900" class Foo end Foo.new.inspect #=> "#<Foo:0x0300c868>" class Bar def initialize @bar = 1 end end Bar.new.inspect #=> "#<Bar:0x0300c868 @bar=1>"
Return this exception’s class name and message.
Round to the nearest integer (by default), returning the result as a BigDecimal
if n is specified, or as an Integer
if it isn’t.
BigDecimal('3.14159').round #=> 3 BigDecimal('8.7').round #=> 9 BigDecimal('-9.9').round #=> -10 BigDecimal('3.14159').round(2).class.name #=> "BigDecimal" BigDecimal('3.14159').round.class.name #=> "Integer"
If n is specified and positive, the fractional part of the result has no more than that many digits.
If n is specified and negative, at least that many digits to the left of the decimal point will be 0 in the result, and return value will be an Integer
.
BigDecimal('3.14159').round(3) #=> 3.142 BigDecimal('13345.234').round(-2) #=> 13300
The value of the optional mode argument can be used to determine how rounding is performed; see BigDecimal.mode
.
Returns self if the value is non-zero, nil otherwise.
Returns a string representation of self.
BigDecimal("1234.5678").inspect #=> "0.12345678e4"
Returns the exponent of the BigDecimal
number, as an Integer
.
If the number can be represented as 0.xxxxxx*10**n where xxxxxx is a string of digits with no leading zeros, then n is the exponent.
Returns true
if rat
is greater than 0.
Returns true
if rat
is less than 0.
Returns rat
rounded to the nearest value with a precision of ndigits
decimal digits (default: 0).
When the precision is negative, the returned value is an integer with at least ndigits.abs
trailing zeros.
Returns a rational when ndigits
is positive, otherwise returns an integer.
Rational(3).round #=> 3 Rational(2, 3).round #=> 1 Rational(-3, 2).round #=> -2 # decimal - 1 2 3 . 4 5 6 # ^ ^ ^ ^ ^ ^ # precision -3 -2 -1 0 +1 +2 Rational('-123.456').round(+1).to_f #=> -123.5 Rational('-123.456').round(-1) #=> -120
The optional half
keyword argument is available similar to Float#round
.
Rational(25, 100).round(1, half: :up) #=> (3/10) Rational(25, 100).round(1, half: :down) #=> (1/5) Rational(25, 100).round(1, half: :even) #=> (1/5) Rational(35, 100).round(1, half: :up) #=> (2/5) Rational(35, 100).round(1, half: :down) #=> (3/10) Rational(35, 100).round(1, half: :even) #=> (2/5) Rational(-25, 100).round(1, half: :up) #=> (-3/10) Rational(-25, 100).round(1, half: :down) #=> (-1/5) Rational(-25, 100).round(1, half: :even) #=> (-1/5)
Returns the value as a string for inspection.
Rational(2).inspect #=> "(2/1)" Rational(-8, 6).inspect #=> "(-4/3)" Rational('1/2').inspect #=> "(1/2)"
Returns a hash of values parsed from string
according to the given format
:
Date._strptime('2001-02-03', '%Y-%m-%d') # => {:year=>2001, :mon=>2, :mday=>3}
For other formats, see Formats for Dates and Times. (Unlike Date.strftime
, does not support flags and width.)
See also strptime(3).
Related: Date.strptime
(returns a Date object).
Returns a new Date object with values parsed from string
, according to the given format
:
Date.strptime('2001-02-03', '%Y-%m-%d') # => #<Date: 2001-02-03> Date.strptime('03-02-2001', '%d-%m-%Y') # => #<Date: 2001-02-03> Date.strptime('2001-034', '%Y-%j') # => #<Date: 2001-02-03> Date.strptime('2001-W05-6', '%G-W%V-%u') # => #<Date: 2001-02-03> Date.strptime('2001 04 6', '%Y %U %w') # => #<Date: 2001-02-03> Date.strptime('2001 05 6', '%Y %W %u') # => #<Date: 2001-02-03> Date.strptime('sat3feb01', '%a%d%b%y') # => #<Date: 2001-02-03>
For other formats, see Formats for Dates and Times. (Unlike Date.strftime
, does not support flags and width.)
See argument start.
See also strptime(3).
Related: Date._strptime
(returns a hash).
Returns true
if self
is a Sunday, false
otherwise.
Returns a string representation of self
:
Date.new(2001, 2, 3).inspect # => "#<Date: 2001-02-03 ((2451944j,0s,0n),+0s,2299161j)>"
Returns a string representation of the date in self
, formatted according the given format
:
Date.new(2001, 2, 3).strftime # => "2001-02-03"
For other formats, see Formats for Dates and Times.
Parses the given representation of date and time with the given template, and returns a hash of parsed elements. _strptime does not support specification of flags and width unlike strftime.
See also strptime(3) and strftime
.
Parses the given representation of date and time with the given template, and creates a DateTime
object. strptime does not support specification of flags and width unlike strftime.
DateTime.strptime('2001-02-03T04:05:06+07:00', '%Y-%m-%dT%H:%M:%S%z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('03-02-2001 04:05:06 PM', '%d-%m-%Y %I:%M:%S %p') #=> #<DateTime: 2001-02-03T16:05:06+00:00 ...> DateTime.strptime('2001-W05-6T04:05:06+07:00', '%G-W%V-%uT%H:%M:%S%z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('2001 04 6 04 05 06 +7', '%Y %U %w %H %M %S %z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('2001 05 6 04 05 06 +7', '%Y %W %u %H %M %S %z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('-1', '%s') #=> #<DateTime: 1969-12-31T23:59:59+00:00 ...> DateTime.strptime('-1000', '%Q') #=> #<DateTime: 1969-12-31T23:59:59+00:00 ...> DateTime.strptime('sat3feb014pm+7', '%a%d%b%y%H%p%z') #=> #<DateTime: 2001-02-03T16:00:00+07:00 ...>
See also strptime(3) and strftime
.
Returns a string representation of self
, formatted according the given +format:
DateTime.now.strftime # => "2022-07-01T11:03:19-05:00"
For other formats, see Formats for Dates and Times: