Is there a built-in function to get the day in last month, same as today? Examples:
2010/05/02 -> 2010/04/02
2010/05/15 -> 2010/04/15
2010/05/31 -> 2010/04/30
Thanks!
You can subtract entire months with <<.
>> d = Date.parse('2010-05-31')
=> #<Date: 4910695/2,0,2299161>
>> d.to_s
=> "2010-05-31"
>> (d<<1).to_s
=> "2010-04-30"
More info
You could do this:
(Date.today - 1.month).strftime("%Y/%m/%d")
You can try using
Time.parse('2010/05/31').months_since(-1).
You could for instance make a time object
old_time = Time.now
Then create a new time object based on that
new_time = Time.local(old_time.year, (old_time.month - 1), old_time.day, old_time.hour, old_time.min, old_time.sec)
However, as deceze pointed out, what is the criterion for 5/31 becoming 4/30?
In irb, 4/31 'overflows' to 5/01.
Ruby's date class allows you to add, subtract days from a particular date.
Related
Hi I would like to subtract time from a CSV array using Ruby
time[0] is 12:12:00AM
time[1] is 12:12:01AM
Here is my code
time_converted = DateTime.parse(time)
difference = time_converted[1].to_i - time_converted[0].to_i
p difference
However, I got 0
p time[0].to_i gives me 12
is there a way to fix this?
You can use Time#strptime to define the format of the parsed string.
In your case the string is %I:%M:%S%p.
%I = 12 hour time
%M = minutes
%S = seconds
%p = AM/PM indicator
So to parse your example:
require 'time'
time = %w(12:12:00AM 12:12:01AM)
parsed_time = time.map { |t| Time.strptime(t, '%I:%M:%S%p').to_i }
parsed_time.last - parsed_time.first
=> 1
Use the Ruby DateTime class and parse your dates into objects of that class.
My project is supposed to fetch specific values from multiple hashes a put those values in a text file. Ideally what I need my code to do is to have every date for the employees be seven days apart, so the text file would look something like this:
"Rachel Thorndike
2017-10-09-T04:29:46-05:00
Stacie Smith
2017-10-16-T04:29:46-05:00"
What this is supposed to do is fetch employee's names and put the time of their "handoff" on the line under them. I looked online and found the DateTime that Ruby features but it looks like whatever I do isn't working. My code is this:
require 'date'
jsonUser["users"].each do |user|
somefile.puts user["user"]["summary"]
print 'Handoff Date + Time: '
parsed = DateTime.strptime(jsonUser["start"], '%d-%m-%Y %H:%M')
utc = parsed.next_day(7).strftime('%d-%m-%Y %H:%M')
puts utc
end
But terminal returns this code with an error 'strptime': invalid date (ArgumentError). Would anybody help me get this code to work the way I want to? Anything that points me to the right direction? With explanations, if it isn't too much.
Thank you so much!
Update
I was able to get the iso8601 to appear under their name. My new code is
require 'date'
jsonUser["users"].each do |user|
somefile.puts user["user"]["summary"]
print 'Handoff Date + Time: '
parsed = DateTime.iso8601(jsonUser["start"])
utc = parsed.next_day(7).iso8601
somefile.puts utc
end
BUT the .next_day method isn't increasing by 7 days that I want too. Thought? I have only got one value that is appearing and that is going under every line. Its the value of jsonUser["start"] + 7 days...so `2017-
10-16T04:29:46-05:00`
This is what parse.next_day(7) gives me.
"Sr Chid
Handoff Date + Time: 2017-10-16T04:29:46-05:00
Ash A
Handoff Date + Time: 2017-10-16T04:29:46-05:00
Ven D
Handoff Date + Time: 2017-10-16T04:29:46-05:00
Abhi S
Handoff Date + Time: 2017-10-16T04:29:46-05:00"
The value of jsonUser["start"] is 2017-10-09T04:29:46-05:00 so the good thing is that it did increase by 7 but it only did it once.
Update for Amadan
require 'date'
date = DateTime.iso8601(jsonUser["start"])
jsonUser["users"].each do |user|
if user["user"]["self"] == nil
nil
else
somefile.puts user["user"]["summary"].gsub(/\w+/, &:capitalize).gsub(/[.]/, ' ')
somefile.print 'Handoff Date + Time: '
date = date.next_day(7)
somefile.puts date.iso8061
end
end
I have three strings, pulled from a database:
"2015-03-18" (the date the event occurs)
"22:00" (the hour an event occurs)
"-05:00" (the UTC offset in the location the event occurs).
I want to combine these three strings to produce a Ruby Time object. I'm doing:
utc_offset = "-05:00"
airtime = "22:00"
airday = "2015-03-18"
year,month,day,hour,minutes = airday.split("-").map(&:to_i) + airtime.split(":").map(&:to_i)
Time.new(year,month,day,hour,minutes,0,utc_offset)
This works; I'm just wondering if it's the correct/standard/idiomatic/clearest way.
By using Time.parse
When ‘time’ is required, Time is extended with additional methods for
parsing and converting Times.
require 'time'
utc_offset = "-05:00"
airtime = "22:00"
airday = "2015-03-18"
time = Time.parse("#{airday} #{airtime} #{utc_offset}")
I think this is the way to do it.
Time.new(*airday.split("-"), *airtime.split(":"), 0, utc_offset)
How about this? http://ruby-doc.org/stdlib-2.1.5/libdoc/time/rdoc/Time.html#method-c-strptime
require 'time'
raw_time = '2015-03-18 22:00'
parsed_time = Time.strptime(raw_time, '%Y-%m-%d %H:%M') # 2015-03-18 22:00:00 +0100
TL;DR: I need to get the difference between HH:MM:SS.ms and HH:MM:SS.ms as HH:MM:SS:ms
What I need:
Here's a tricky one. I'm trying to calculate the difference between two timestamps such as the following:
In: 00:00:10.520
Out: 00:00:23.720
Should deliver:
Diff: 00:00:13.200
I thought I'd parse the times into actual Time objects and use the difference there. This works great in the previous case, and returns 00:0:13.200.
What doesn't work:
However, for some, this doesn't work right, as Ruby uses usec instead of msec:
In: 00:2:22.760
Out: 00:2:31.520
Diff: 00:0:8.999760
Obviously, the difference should be 00:00:8:760 and not 00:00:8.999760. I'm really tempted to just tdiff.usec.to_s.gsub('999','') ……
My code so far:
Here's my code so far (these are parsed from the input strings like "0:00:10:520").
tin_first, tin_second = ins.split(".")
tin_hours, tin_minutes, tin_seconds = tin_first.split(":")
tin_usec = tin_second * 1000
tin = Time.gm(0, 1, 1, tin_hours, tin_minutes, tin_seconds, tin_usec)
The same happens for tout. Then:
tdiff = Time.at(tout-tin)
For the output, I use:
"00:#{tdiff.min}:#{tdiff.sec}.#{tdiff.usec}"
Is there any faster way to do this? Remember, I just want to have the difference between two times. What am I missing?
I'm using Ruby 1.9.3p6 at the moment.
Using Time:
require 'time' # Needed for Time.parse
def time_diff(time1_str, time2_str)
t = Time.at( Time.parse(time2_str) - Time.parse(time1_str) )
(t - t.gmt_offset).strftime("%H:%M:%S.%L")
end
out_time = "00:00:24.240"
in_time = "00:00:14.520"
p time_diff(in_time, out_time)
#=> "00:00:09.720"
Here's a solution that doesn't rely on Time:
def slhck_diff( t1, t2 )
ms_to_time( time_as_ms(t2) - time_as_ms(t1) )
end
# Converts "00:2:22.760" to 142760
def time_as_ms( time_str )
re = /(\d+):(\d+):(\d+)(?:\.(\d+))?/
parts = time_str.match(re).to_a.map(&:to_i)
parts[4]+(parts[3]+(parts[2]+parts[1]*60)*60)*1000
end
# Converts 142760 to "00:02:22.760"
def ms_to_time(ms)
m = ms.floor / 60000
"%02i:%02i:%06.3f" % [ m/60, m%60, ms/1000.0 % 60 ]
end
t1 = "00:00:10.520"
t2 = "01:00:23.720"
p slhck_diff(t1,t2)
#=> "01:00:13.200"
t1 = "00:2:22.760"
t2 = "00:2:31.520"
p slhck_diff(t1,t2)
#=> "00:00:08.760"
I figured the following could work:
out_time = "00:00:24.240"
in_time = "00:00:14.520"
diff = Time.parse(out_time) - Time.parse(in_time)
Time.at(diff).strftime("%H:%M:%S.%L")
# => "01:00:09.720"
It does print 01 for the hour, which I don't really understand.
In the meantime, I used:
Time.at(diff).strftime("00:%M:%S.%L")
# => "00:00:09.720"
Any answer that does this better will get an upvote or the accept, of course.
in_time = "00:02:22.760"
out_time = "00:02:31.520"
diff = (Time.parse(out_time) - Time.parse(in_time))*1000
puts diff
OUTPUT:
8760.0 millliseconds
Time.parse(out_time) - Time.parse(in_time) gives the result in seconds so multiplied by 1000 to convert into milliseconds.
I have a calendar screen where I want to display the hours of the day like this:
12:00am
1:00am
2:00am
..
4:00pm
5:00pm
etc.
Being a total Ruby noob, I was wondering if anyone could help me figure out the simplest way to display this.
#!/usr/bin/env ruby
# without using actual `Date` objects ...
p ["12:00am"] + (1..11).map {|h| "#{h}:00am"}.to_a +
["12:00pm"] + (1..11).map {|h| "#{h}:00pm"}.to_a
["12:00am", "1:00am", "2:00am", "3:00am", "4:00am", "5:00am", "6:00am",
"7:00am", "8:00am", "9:00am", "10:00am", "11:00am", "12:00pm", "1:00pm",
"2:00pm", "3:00pm", "4:00pm", "5:00pm", "6:00pm", "7:00pm", "8:00pm",
"9:00pm", "10:00pm", "11:00pm"]
Or using actual DateTime objects and %I:%M%p as format:
#!/usr/bin/env ruby
require "Date"
for hour in 0..23 do
d = DateTime.new(2010, 1, 1, hour, 0, 0)
p d.strftime("%I:%M%p")
end
Which would print:
"12:00AM"
"01:00AM"
"02:00AM"
"03:00AM"
"04:00AM"
"05:00AM"
"06:00AM"
"07:00AM"
"08:00AM"
"09:00AM"
"10:00AM"
"11:00AM"
"12:00PM"
"01:00PM"
"02:00PM"
"03:00PM"
"04:00PM"
"05:00PM"
"06:00PM"
"07:00PM"
"08:00PM"
"09:00PM"
"10:00PM"
"11:00PM"
You could generate these like this:
array = ['12:00am'] + (1..11).map {|h| "#{h}:00am"} + ['12:00pm'] + (1..11).map {|h| "#{h}:00pm"}
or simply write out the array (this is more efficient):
array = ["12:00am", "1:00am", "2:00am", "3:00am", "4:00am", "5:00am", "6:00am", "7:00am", "8:00am", "9:00am", "10:00am", "11:00am", "12:00pm", "1:00pm", "2:00pm", "3:00pm", "4:00pm", "5:00pm", "6:00pm", "7:00pm", "8:00pm", "9:00pm", "10:00pm", "11:00pm"]
You can then print these however you want, eg.
array.each do |el|
puts el
end