Attendance Logic

file.rb

=begin
 Help with Logic
=end
allRecords = Attendance.pluck(:date, :presence).map { |attendance, presence| [attendance.strftime('%B'), presence] } #=> [['November',true],['November',false],['November',true],['December', true], ['December', false], ['January',false], ['January',true]]
monthFilter = allRecords.uniq.map { |month| [month[0]] } #=> ['November','November', 'November', 'December', 'December', 'January','January']
months = monthFilter.uniq #=> ['November','December','January']

# Expected To do the following:
# To fetch all the records and count the number of true presence with false presence per month. Then get a percentage of true / total in each month

Try creating a hash of each month, i.e

months = Hash.new()
months.default=[]
allRecords = Attendance.pluck(:date, :presence).map { |attendance, presence| [attendance.strftime('%B'), presence] } #=> [['November',true],['November',false],['November',true],['December', true], ['December', false], ['January',false], ['January',true]]

Collate the records per month.

allRecords.each.map |record|
months[record[0]].push(record)
end

then make a function that takes each key of months and returns a value based on percentaging the array with whatever your business rules are.

all_records.group_by(&:first).map { |k, v| trues, falses = v.partition(&:last); [k, "#{falses.size * 100  / trues.size}%"] }
#=> [["November", "50%"], ["December", "100%"], ["January", "100%"]]

Adjusted the code to this:

all_records = Attendance.pluck(:date, :presence).map { |attendance, presence| [attendance.strftime('%B'), presence] } #=> [['November',true],['November',false],['November',true],['December', true], ['December', false], ['January',false], ['January',true]]
    @attendances = all_records.group_by(&:first).map { |k, v| trues, falses = v.partition(&:last); [k, "#{falses.size * 100  / trues.size}%"] } #=> [["November", "0%"], ["December", "0%"], ["January", "0%"]]

But now get 0% on all

In the end, I realized it was the percentage logic that needed to be corrected. So I had this instead

[k, "#{(Float(trues.size)/ (Float(falses.size) + Float(trues.size)) * 100).round}%"]