Script to generate Ledger entries that distribute a cost over several days

distribute-cost.py

#!/usr/bin/env python
#
# Generate Ledger entries that distribute a cost over several days.
# http://www.ledger-cli.org/
#
# Example usage:
# ./bin/distribute-cost Expenses:Food:Groceries 500 TWD 2017/02/05 7
#
# -- oskarth

import sys
from datetime import datetime, timedelta

if len(sys.argv) != 6:
   print "Wrong number of arguments"
   print "Example usage:"
   print "./distribute-cost Expenses:Misc:Buffer 150 USD 2017/02/05 7"
   sys.exit(1)

category = sys.argv[1]
total    = float(sys.argv[2])
currency = sys.argv[3]
date     = datetime.strptime(sys.argv[4], "%Y/%m/%d")
days     = int(sys.argv[5])

part = (total*100 // days) / 100
rest = (total*100 % days) / 100
d1 = datetime.strftime(date, "%Y/%m/%d")

part_str = "{:.2f}".format(part)
rest_str ="{:.2f}".format(rest)

if not (abs(float(part * days + rest) - total) <= 0.01):
   print "ERROR: Part and rest don't add up"
   print float(part * days + rest), "vs", total
   sys.exit(1)

print "".join(["    ", category, "      ", rest_str,
               " ", currency, " ; [=", d1, "]"])

for n in range(days):
   dn = datetime.strftime(date + timedelta(days=n), "%Y/%m/%d")
   print "".join(["    ", category, "      ", part_str,
                  " ", currency, " ; [=", dn, "]"])

Example output

➜  finance git:(master) ✗ ./bin/distribute-cost Expenses:Misc:Buffer 150 USD 2017/02/01 28
    Expenses:Misc:Buffer      0.20 USD ; [=2017/02/01]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/01]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/02]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/03]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/04]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/05]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/06]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/07]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/08]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/09]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/10]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/11]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/12]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/13]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/14]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/15]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/16]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/17]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/18]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/19]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/20]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/21]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/22]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/23]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/24]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/25]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/26]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/27]
    Expenses:Misc:Buffer      5.35 USD ; [=2017/02/28]