Ruby group_by return array

Question

I have a block of code that looks like

runs.this_month.group_by(&:week).each do |week,runs|
  puts 'week' + week
  puts runs.size
end

Right now it just returns
week00
1
week 03
1

What I am hoping to have this loop generate is an object that has 0's if that week has no runs. For example, if I have the month of January, and there is one run the first week,no runs the second week, one run the 3rd week,and no runs the last week, ideally it would return something that looks like

[1,0,1,0]

I think my issue is with the group_by() enumerable not knowing how many weeks there are in a month for example.

Also FWIW the this_month scope looks for all runs with :created_at this month. That bit works as expected and returns a group of all of the runs from this month.

edit1:
This is sloppy, but seems to be working:

month = [0,0,0,0]
weeks = [0,1,2,3]
runs.this_month.group_by(&:week).each do |week,runs|
  if weeks.include? (week[0].to_i)
    month[week.to_i] = runs
  end
end

working means month looks like [ActiveRecord...,0,ActiveRecord...,0]

The group_by is certainly part of your problem. What have you tried to resolve that issue? Simplest way would be to just add empty entries for the weeks that are missing. — Nick Veys
– Nick Veys, Commented Jan 23, 2015 at 22:39
@NickVeys- I have tried checking the value of "week" (00 or 03 in this case) against an array of [0,1,2,3] to see if that week belongs there, if so put the run in that element's position...if that makes sense — Alex Neigher
– Alex Neigher, Commented Jan 23, 2015 at 22:42
Ok, did that help? The code you posted just prints things. It's confusing because you are asking for something when it looks like your code doesn't even attempt to do it. You get much better responses on this site if you try but fail, and then ask for help with your current solution. — Nick Veys
– Nick Veys, Commented Jan 23, 2015 at 22:46
Yeah code doesn't work well in comments, just edit your question. — Nick Veys
– Nick Veys, Commented Jan 23, 2015 at 22:47
yup, sorry about that. Should have formatted my question more clearly. The edit has a bit more clarification — Alex Neigher
– Alex Neigher, Commented Jan 23, 2015 at 22:50

Alexander · Accepted Answer · 2015-01-24 19:14:01Z

1

I guess that weeks are integers 0, 1, 2, 3.

default_stats = { 0: [], 1: [], 2: [], 3: [] }
runs.this_month.group_by(&:week).reverse_merge(default_stats)

edited Jan 24, 2015 at 19:14

answered Jan 24, 2015 at 2:12

Alexander

2,5781 gold badge31 silver badges34 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Ruby group_by return array

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related