How do I convert a string into a Time object? - ruby-on-rails

Question

I searched for my problem and got a lot of solutions, but unfortunately none satisfy my need.
My problem is, I have two or more strings, and I want to convert those strings into times, and add them:
time1 = "10min 43s"
time2 = "32min 30s"
The output will be: 43min 13s
My attempted solution is:
time1 = "10min 43s"
d1=DateTime.strptime(time1, '%M ')
# Sat, 02 Nov 2013 00:10:00 +0000
time2 = "32min 30s"
d2=DateTime.strptime(time2, '%M ')
# Sat, 02 Nov 2013 00:32:00 +0000
Then I can't progress.

Answer 1

There are many ways to do this. Here's another:
time1 = "10min 43s"
time2 = "32min 30s"
def get_mins_and_secs(time_str)
time_str.scan(/\d+/).map(&:to_i)
#=> [10, 43] for time_str = time1, [32, 30] for time_str = time2
end
min, sec = get_mins_and_secs(time1)
min2, sec2 = get_mins_and_secs(time2)
min += min2
sec += sec2
if sec > 59
min += 1
sec -= 60
end
puts "#{min}min #{sec}sec"
Let's consider what's happening here. Firstly, you need to extract the minutes and seconds from the time strings. I made a method to do that:
def get_mins_and_secs(time_str)
time_str.scan(/\d+/).map(&:to_i)
#=> [10, 43] for time_str = time1, [32, 30] for time_str = time2
end
For time_str = "10min 43s", we apply the String#scan method to extract the two numbers as strings:
"10min 43s".scan(/\d+/) # => ["10", "43"]
Array#map is then used to convert these two strings to integers
["10", "43"].map {|e| e.to_i} # => [10, 43]
This can be written more succinctly as
["10", "43"].map(&:to_i} # => [10, 43]
By chaining map to to scan we obtain
"10min 43s".scan(/\d+/).map(&:to_i} # => [10, 43]
The array [10, 43] is returned and received (deconstructed) by the variables min and sec:
min, sec = get_mins_and_secs(time_str)
The rest is straightforward.

Answer 2

Here's a simple solution assuming that the format stays the same:
time1 = "10min 43s"
time2 = "32min 30s"
strings = [time1, time2]
total_time = strings.inject(0) do |sum, entry|
minutes, seconds = entry.split(' ')
minutes = minutes.gsub("min", "").to_i.send(:minutes)
seconds = seconds.gsub("s", "").to_i.send(:seconds)
sum + minutes + seconds
end
puts "#{total_time/60}min #{total_time%60}s"

Answer 3

Something like the following should do the trick:
# split the string on all the integers in the string
def to_seconds(time_string)
min, sec = time_string.gsub(/\d+/).map(&:to_i)
min.minutes + sec.seconds
end
# Divide the seconds with 60 to get minutes and format the output.
def to_time_str(seconds)
minutes = seconds / 60
seconds = seconds % 60
format("%02dmin %02dsec", minutes, seconds)
end
time_in_seconds1 = to_seconds("10min 43s")
time_in_seconds2 = to_seconds("32min 30s")
to_time_str(time_in_seconds1 + time_in_seconds2)

Answer 4

My solution that takes any number of time strings and return the sum in the same format:
def add_times(*times)
digits = /\d+/
total_time = times.inject(0){|sum, entry|
m, s = entry.scan(digits).map(&:to_i)
sum + m*60 + s
}.divmod(60)
times.first.gsub(digits){total_time.shift}
end
p add_times("10min 43s", "32min 55s", "1min 2s") #=> "44min, 40s"
p add_times("10:43", "32:55") #=> "38:43"