"Rata Die". Counting Days since...

 

Counting Days since...

https://en.wikipedia.org/wiki/Rata_Die

# col1 is an exported column of dates

lastDay = 54 # last row in the column sorted by the date

daysSince(x) = Dates.datetime2rata(x) - Dates.datetime2rata(col1[lastDay])

arrayDays = Array{Int64}(undef, lastDay) # array size is 54

for i = 1:lastDay

    arrayDays[i] = daysSince(col1[i])

end

arrayDays

Output:

54-element Array{Int64,1}:
 613
 606
 599
 592
 582
 575
 568
 554
 547
 540
 533
 526
 512
   ⋮