Returns rat
truncated (toward zero) to 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).truncate #=> 3 Rational(2, 3).truncate #=> 0 Rational(-3, 2).truncate #=> -1 # decimal - 1 2 3 . 4 5 6 # ^ ^ ^ ^ ^ ^ # precision -3 -2 -1 0 +1 +2 Rational('-123.456').truncate(+1).to_f #=> -123.4 Rational('-123.456').truncate(-1) #=> -120
Returns a simpler approximation of the value if the optional argument eps
is given (rat-|eps| <= result <= rat+|eps|), self otherwise.
r = Rational(5033165, 16777216) r.rationalize #=> (5033165/16777216) r.rationalize(Rational('0.01')) #=> (3/10) r.rationalize(Rational('0.1')) #=> (1/3)
Returns true if the date is Sunday.
Returns true if the date is Monday.
Returns true if the date is Tuesday.
Returns true if the date is Wednesday.
Returns true if the date is Thursday.
Returns true if the date is Friday.
Returns the Julian day number denoting the day of calendar reform.
Date.new(2001,2,3).start #=> 2299161.0 Date.new(2001,2,3,Date::GREGORIAN).start #=> -Infinity
This method is equivalent to new_start
(Date::ITALY
).
Creates a new Time
object with the value given by time
, the given number of seconds_with_frac
, or seconds
and microseconds_with_frac
since the Epoch. seconds_with_frac
and microseconds_with_frac
can be an Integer
, Float
, Rational
, or other Numeric
.
If in
argument is given, the result is in that timezone or UTC offset, or if a numeric argument is given, the result is in local time. The in
argument accepts the same types of arguments as tz
argument of Time.new
: string, number of seconds, or a timezone object.
Time.at(0) #=> 1969-12-31 18:00:00 -0600 Time.at(Time.at(0)) #=> 1969-12-31 18:00:00 -0600 Time.at(946702800) #=> 1999-12-31 23:00:00 -0600 Time.at(-284061600) #=> 1960-12-31 00:00:00 -0600 Time.at(946684800.2).usec #=> 200000 Time.at(946684800, 123456.789).nsec #=> 123456789 Time.at(946684800, 123456789, :nsec).nsec #=> 123456789 Time.at(1582721899, in: "+09:00") #=> 2020-02-26 21:58:19 +0900 Time.at(1582721899, in: "UTC") #=> 2020-02-26 12:58:19 UTC Time.at(1582721899, in: "C") #=> 2020-02-26 13:58:19 +0300 Time.at(1582721899, in: 32400) #=> 2020-02-26 21:58:19 +0900 require 'tzinfo' Time.at(1582721899, in: TZInfo::Timezone.get('Europe/Kiev')) #=> 2020-02-26 14:58:19 +0200
Returns the day of the month (1..31) for time.
t = Time.now #=> 2007-11-19 08:27:03 -0600 t.day #=> 19 t.mday #=> 19
Returns the day of the month (1..31) for time.
t = Time.now #=> 2007-11-19 08:27:03 -0600 t.day #=> 19 t.mday #=> 19
Returns an integer representing the day of the week, 0..6, with Sunday == 0.
t = Time.now #=> 2007-11-20 02:35:35 -0600 t.wday #=> 2 t.sunday? #=> false t.monday? #=> false t.tuesday? #=> true t.wednesday? #=> false t.thursday? #=> false t.friday? #=> false t.saturday? #=> false
Returns an integer representing the day of the year, 1..366.
t = Time.now #=> 2007-11-19 08:32:31 -0600 t.yday #=> 323
Returns true
if time represents Sunday.
t = Time.local(1990, 4, 1) #=> 1990-04-01 00:00:00 -0600 t.sunday? #=> true
Returns true
if time represents Monday.
t = Time.local(2003, 8, 4) #=> 2003-08-04 00:00:00 -0500 t.monday? #=> true
Returns true
if time represents Tuesday.
t = Time.local(1991, 2, 19) #=> 1991-02-19 00:00:00 -0600 t.tuesday? #=> true
Returns true
if time represents Wednesday.
t = Time.local(1993, 2, 24) #=> 1993-02-24 00:00:00 -0600 t.wednesday? #=> true