Works similar to parse
except that instead of using a heuristic to detect the format of the input string, you provide a second argument that describes the format of the string.
If a block is given, the year described in date
is converted by the block. For example:
Time.strptime(...) {|y| y < 100 ? (y >= 69 ? y + 1900 : y + 2000) : y}
Below is a list of the formatting options:
The abbreviated weekday name (“Sun”)
The full weekday name (“Sunday”)
The abbreviated month name (“Jan”)
The full month name (“January”)
The preferred local date and time representation
Century (20 in 2009)
Day of the month (01..31)
Date
(%m/%d/%y)
Day of the month, blank-padded ( 1..31)
Equivalent to %Y-%m-%d (the ISO 8601 date format)
The last two digits of the commercial year
The week-based year according to ISO-8601 (week 1 starts on Monday and includes January 4)
Equivalent to %b
Hour of the day, 24-hour clock (00..23)
Hour of the day, 12-hour clock (01..12)
Day of the year (001..366)
hour, 24-hour clock, blank-padded ( 0..23)
hour, 12-hour clock, blank-padded ( 0..12)
Millisecond of the second (000..999)
Month of the year (01..12)
Minute of the hour (00..59)
Newline (n)
Fractional seconds digits
Meridian indicator (“AM” or “PM”)
Meridian indicator (“am” or “pm”)
time, 12-hour (same as %I:%M:%S %p)
time, 24-hour (%H:%M)
Number of seconds since 1970-01-01 00:00:00 UTC.
Second of the minute (00..60)
Tab character (t)
time, 24-hour (%H:%M:%S)
Day of the week as a decimal, Monday being 1. (1..7)
Week number of the current year, starting with the first Sunday as the first day of the first week (00..53)
VMS date (%e-%b-%Y)
Week number of year according to ISO 8601 (01..53)
Week number of the current year, starting with the first Monday as the first day of the first week (00..53)
Day of the week (Sunday is 0, 0..6)
Preferred representation for the date alone, no time
Preferred representation for the time alone, no date
Year without a century (00..99)
Year which may include century, if provided
Time
zone as hour offset from UTC (e.g. +0900)
Time
zone name
Literal “%” character
date(1) (%a %b %e %H:%M:%S %Z %Y)
require 'time' Time.strptime("2000-10-31", "%Y-%m-%d") #=> 2000-10-31 00:00:00 -0500
You must require ‘time’ to use this method.
Returns the value of time as an integer number of seconds since the Epoch.
If time contains subsecond, they are truncated.
t = Time.now #=> 2020-07-21 01:41:29.746012609 +0900 t.to_i #=> 1595263289
Returns the value of time as a floating point number of seconds since the Epoch. The return value approximate the exact value in the Time
object because floating point numbers cannot represent all rational numbers exactly.
t = Time.now #=> 2020-07-20 22:00:29.38740268 +0900 t.to_f #=> 1595250029.3874028 t.to_i #=> 1595250029
Note that IEEE 754 double is not accurate enough to represent the exact number of nanoseconds since the Epoch. (IEEE 754 double has 53bit mantissa. So it can represent exact number of nanoseconds only in ‘2 ** 53 / 1_000_000_000 / 60 / 60 / 24 = 104.2` days.) When Ruby uses a nanosecond-resolution clock function, such as clock_gettime
of POSIX, to obtain the current time, Time#to_f
can lost information of a Time
object created with Time.now
.
Returns the value of time as a rational number of seconds since the Epoch.
t = Time.now #=> 2020-07-20 22:03:45.212167333 +0900 t.to_r #=> (1595250225212167333/1000000000)
This method is intended to be used to get an accurate value representing the seconds (including subsecond) since the Epoch.
Returns a string representing time. Equivalent to calling strftime
with the appropriate format string.
t = Time.now t.to_s #=> "2012-11-10 18:16:12 +0100" t.strftime "%Y-%m-%d %H:%M:%S %z" #=> "2012-11-10 18:16:12 +0100" t.utc.to_s #=> "2012-11-10 17:16:12 UTC" t.strftime "%Y-%m-%d %H:%M:%S UTC" #=> "2012-11-10 17:16:12 UTC"
Returns a ten-element array of values for time:
[sec, min, hour, day, month, year, wday, yday, isdst, zone]
See the individual methods for an explanation of the valid ranges of each value. The ten elements can be passed directly to Time.utc
or Time.local
to create a new Time
object.
t = Time.now #=> 2007-11-19 08:36:01 -0600 now = t.to_a #=> [1, 36, 8, 19, 11, 2007, 1, 323, false, "CST"]
Floors subsecond to a given precision in decimal digits (0 digits by default). It returns a new Time
object. ndigits
should be zero or a positive integer.
t = Time.utc(2010,3,30, 5,43,25.123456789r) t #=> 2010-03-30 05:43:25.123456789 UTC t.floor #=> 2010-03-30 05:43:25 UTC t.floor(0) #=> 2010-03-30 05:43:25 UTC t.floor(1) #=> 2010-03-30 05:43:25.1 UTC t.floor(2) #=> 2010-03-30 05:43:25.12 UTC t.floor(3) #=> 2010-03-30 05:43:25.123 UTC t.floor(4) #=> 2010-03-30 05:43:25.1234 UTC t = Time.utc(1999,12,31, 23,59,59) (t + 0.4).floor #=> 1999-12-31 23:59:59 UTC (t + 0.9).floor #=> 1999-12-31 23:59:59 UTC (t + 1.4).floor #=> 2000-01-01 00:00:00 UTC (t + 1.9).floor #=> 2000-01-01 00:00:00 UTC t = Time.utc(1999,12,31, 23,59,59) (t + 0.123456789).floor(4) #=> 1999-12-31 23:59:59.1234 UTC
Returns true
if time occurs during Daylight Saving Time
in its time zone.
# CST6CDT: Time.local(2000, 1, 1).zone #=> "CST" Time.local(2000, 1, 1).isdst #=> false Time.local(2000, 1, 1).dst? #=> false Time.local(2000, 7, 1).zone #=> "CDT" Time.local(2000, 7, 1).isdst #=> true Time.local(2000, 7, 1).dst? #=> true # Asia/Tokyo: Time.local(2000, 1, 1).zone #=> "JST" Time.local(2000, 1, 1).isdst #=> false Time.local(2000, 1, 1).dst? #=> false Time.local(2000, 7, 1).zone #=> "JST" Time.local(2000, 7, 1).isdst #=> false Time.local(2000, 7, 1).dst? #=> false
Returns true
if time occurs during Daylight Saving Time
in its time zone.
# CST6CDT: Time.local(2000, 1, 1).zone #=> "CST" Time.local(2000, 1, 1).isdst #=> false Time.local(2000, 1, 1).dst? #=> false Time.local(2000, 7, 1).zone #=> "CDT" Time.local(2000, 7, 1).isdst #=> true Time.local(2000, 7, 1).dst? #=> true # Asia/Tokyo: Time.local(2000, 1, 1).zone #=> "JST" Time.local(2000, 1, 1).isdst #=> false Time.local(2000, 1, 1).dst? #=> false Time.local(2000, 7, 1).zone #=> "JST" Time.local(2000, 7, 1).isdst #=> false Time.local(2000, 7, 1).dst? #=> false
Returns the offset in seconds between the timezone of time and UTC.
t = Time.gm(2000,1,1,20,15,1) #=> 2000-01-01 20:15:01 UTC t.gmt_offset #=> 0 l = t.getlocal #=> 2000-01-01 14:15:01 -0600 l.gmt_offset #=> -21600
Formats time according to the directives in the given format string.
The directives begin with a percent (%) character. Any text not listed as a directive will be passed through to the output string.
The directive consists of a percent (%) character, zero or more flags, optional minimum field width, optional modifier and a conversion specifier as follows:
%<flags><width><modifier><conversion>
Flags:
- don't pad a numerical output _ use spaces for padding 0 use zeros for padding ^ upcase the result string # change case : use colons for %z
The minimum field width specifies the minimum width.
The modifiers are “E” and “O”. They are ignored.
Format directives:
Date (Year, Month, Day): %Y - Year with century if provided, will pad result at least 4 digits. -0001, 0000, 1995, 2009, 14292, etc. %C - year / 100 (rounded down such as 20 in 2009) %y - year % 100 (00..99) %m - Month of the year, zero-padded (01..12) %_m blank-padded ( 1..12) %-m no-padded (1..12) %B - The full month name (``January'') %^B uppercased (``JANUARY'') %b - The abbreviated month name (``Jan'') %^b uppercased (``JAN'') %h - Equivalent to %b %d - Day of the month, zero-padded (01..31) %-d no-padded (1..31) %e - Day of the month, blank-padded ( 1..31) %j - Day of the year (001..366) Time (Hour, Minute, Second, Subsecond): %H - Hour of the day, 24-hour clock, zero-padded (00..23) %k - Hour of the day, 24-hour clock, blank-padded ( 0..23) %I - Hour of the day, 12-hour clock, zero-padded (01..12) %l - Hour of the day, 12-hour clock, blank-padded ( 1..12) %P - Meridian indicator, lowercase (``am'' or ``pm'') %p - Meridian indicator, uppercase (``AM'' or ``PM'') %M - Minute of the hour (00..59) %S - Second of the minute (00..60) %L - Millisecond of the second (000..999) The digits under millisecond are truncated to not produce 1000. %N - Fractional seconds digits, default is 9 digits (nanosecond) %3N millisecond (3 digits) %6N microsecond (6 digits) %9N nanosecond (9 digits) %12N picosecond (12 digits) %15N femtosecond (15 digits) %18N attosecond (18 digits) %21N zeptosecond (21 digits) %24N yoctosecond (24 digits) The digits under the specified length are truncated to avoid carry up. Time zone: %z - Time zone as hour and minute offset from UTC (e.g. +0900) %:z - hour and minute offset from UTC with a colon (e.g. +09:00) %::z - hour, minute and second offset from UTC (e.g. +09:00:00) %Z - Abbreviated time zone name or similar information. (OS dependent) Weekday: %A - The full weekday name (``Sunday'') %^A uppercased (``SUNDAY'') %a - The abbreviated name (``Sun'') %^a uppercased (``SUN'') %u - Day of the week (Monday is 1, 1..7) %w - Day of the week (Sunday is 0, 0..6) ISO 8601 week-based year and week number: The first week of YYYY starts with a Monday and includes YYYY-01-04. The days in the year before the first week are in the last week of the previous year. %G - The week-based year %g - The last 2 digits of the week-based year (00..99) %V - Week number of the week-based year (01..53) Week number: The first week of YYYY that starts with a Sunday or Monday (according to %U or %W). The days in the year before the first week are in week 0. %U - Week number of the year. The week starts with Sunday. (00..53) %W - Week number of the year. The week starts with Monday. (00..53) Seconds since the Epoch: %s - Number of seconds since 1970-01-01 00:00:00 UTC. Literal string: %n - Newline character (\n) %t - Tab character (\t) %% - Literal ``%'' character Combination: %c - date and time (%a %b %e %T %Y) %D - Date (%m/%d/%y) %F - The ISO 8601 date format (%Y-%m-%d) %v - VMS date (%e-%^b-%4Y) %x - Same as %D %X - Same as %T %r - 12-hour time (%I:%M:%S %p) %R - 24-hour time (%H:%M) %T - 24-hour time (%H:%M:%S)
This method is similar to strftime() function defined in ISO C and POSIX.
While all directives are locale independent since Ruby 1.9, %Z is platform dependent. So, the result may differ even if the same format string is used in other systems such as C.
%z is recommended over %Z. %Z doesn’t identify the timezone. For example, “CST” is used at America/Chicago (-06:00), America/Havana (-05:00), Asia/Harbin (+08:00), Australia/Darwin (+09:30) and Australia/Adelaide (+10:30). Also, %Z is highly dependent on the operating system. For example, it may generate a non ASCII string on Japanese Windows, i.e. the result can be different to “JST”. So the numeric time zone offset, %z, is recommended.
Examples:
t = Time.new(2007,11,19,8,37,48,"-06:00") #=> 2007-11-19 08:37:48 -0600 t.strftime("Printed on %m/%d/%Y") #=> "Printed on 11/19/2007" t.strftime("at %I:%M %p") #=> "at 08:37 AM"
Various ISO 8601 formats:
%Y%m%d => 20071119 Calendar date (basic) %F => 2007-11-19 Calendar date (extended) %Y-%m => 2007-11 Calendar date, reduced accuracy, specific month %Y => 2007 Calendar date, reduced accuracy, specific year %C => 20 Calendar date, reduced accuracy, specific century %Y%j => 2007323 Ordinal date (basic) %Y-%j => 2007-323 Ordinal date (extended) %GW%V%u => 2007W471 Week date (basic) %G-W%V-%u => 2007-W47-1 Week date (extended) %GW%V => 2007W47 Week date, reduced accuracy, specific week (basic) %G-W%V => 2007-W47 Week date, reduced accuracy, specific week (extended) %H%M%S => 083748 Local time (basic) %T => 08:37:48 Local time (extended) %H%M => 0837 Local time, reduced accuracy, specific minute (basic) %H:%M => 08:37 Local time, reduced accuracy, specific minute (extended) %H => 08 Local time, reduced accuracy, specific hour %H%M%S,%L => 083748,000 Local time with decimal fraction, comma as decimal sign (basic) %T,%L => 08:37:48,000 Local time with decimal fraction, comma as decimal sign (extended) %H%M%S.%L => 083748.000 Local time with decimal fraction, full stop as decimal sign (basic) %T.%L => 08:37:48.000 Local time with decimal fraction, full stop as decimal sign (extended) %H%M%S%z => 083748-0600 Local time and the difference from UTC (basic) %T%:z => 08:37:48-06:00 Local time and the difference from UTC (extended) %Y%m%dT%H%M%S%z => 20071119T083748-0600 Date and time of day for calendar date (basic) %FT%T%:z => 2007-11-19T08:37:48-06:00 Date and time of day for calendar date (extended) %Y%jT%H%M%S%z => 2007323T083748-0600 Date and time of day for ordinal date (basic) %Y-%jT%T%:z => 2007-323T08:37:48-06:00 Date and time of day for ordinal date (extended) %GW%V%uT%H%M%S%z => 2007W471T083748-0600 Date and time of day for week date (basic) %G-W%V-%uT%T%:z => 2007-W47-1T08:37:48-06:00 Date and time of day for week date (extended) %Y%m%dT%H%M => 20071119T0837 Calendar date and local time (basic) %FT%R => 2007-11-19T08:37 Calendar date and local time (extended) %Y%jT%H%MZ => 2007323T0837Z Ordinal date and UTC of day (basic) %Y-%jT%RZ => 2007-323T08:37Z Ordinal date and UTC of day (extended) %GW%V%uT%H%M%z => 2007W471T0837-0600 Week date and local time and difference from UTC (basic) %G-W%V-%uT%R%:z => 2007-W47-1T08:37-06:00 Week date and local time and difference from UTC (extended)
Deletes all entries for which the code block returns true. Returns self.
Converts the contents of the database to an in-memory Hash
, then calls Hash#reject
with the specified code block, returning a new Hash
.
Replaces the contents of the database with the contents of the specified object. Takes any object which implements the each_pair
method, including Hash
and DBM
objects.
Converts the contents of the database to an array of [key, value] arrays, and returns it.
Returns the values for this struct as an Array
.
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.to_a[1] #=> "123 Maple, Anytown NC"
Returns a Hash
containing the names and values for the struct’s members.
If a block is given, the results of the block on each pair of the receiver will be used as pairs.
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.to_h[:address] #=> "123 Maple, Anytown NC" joe.to_h{|name, value| [name.upcase, value.to_s.upcase]}[:ADDRESS] #=> "123 MAPLE, ANYTOWN NC"
Returns the values for this struct as an Array
.
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.to_a[1] #=> "123 Maple, Anytown NC"
Returns a description of this struct as a string.
Returns number of bytes that can be read without blocking. Returns zero if no information available.
Returns true
if input available without blocking, or false
.