# Version 1.0 Ernie P. Adorio
#
# 1. Data source rows as tuples, fields should form a hierarchy.
# but the rows do not have to be in sorted order.
# (Region, city, value)
records = [ ('England', 'Manchester', 45600),
('Scotland', 'Edinburgh', 20000),
('England', 'London', 90000),
('Scotland', 'Glasgow', 12500),
('Wales', 'Cardiff', 29700),
('England', 'Liverpool', 29700),
('Scotland', 'Edinburgh', 1000),
('Wales', 'Bangor', 12800),
('Scotland', 'Glasgow', 13400),
('England', 'Liverpool', 30000)]
# 2. Hierarchy levels and index of value to summarize.
maxlevel = 2 # Maximum hierarchy levels Region/city.
valueIndex = 2 # Index of value to summarize in data tuple.
# 3. Summaries in dictionary format.
Dlevels = {}
for rec in records:
v = rec[valueIndex]
for i in range(maxlevel): # handle the sublevels
key = rec[:i+1]
if key not in Dlevels:
Dlevels[key] = v
else:
Dlevels[key] += v
# 4. Schwartzian transform
Tlevels = []
for key in Dlevels:
value = Dlevels[key]
Tlevels.append((key, value))
Tlevels.sort()
# 5. Reporting (must be tailored to your actual requirements).
Total = 0
for (key, value) in enumerate(Tlevels):
location = value[0]
amt = value[1]
L = len(location)
if L == 1: # Major category.
Region = location[0]
print Region, " \t", amt
Total += amt
else:
print " " * L,
city = location[1]
print city, "\t\t", amt
print "=" * 10
print "Total \t", Total
"""
When the program is run, it outputs
England 195300
Liverpool 59700
London 90000
Manchester 45600
Scotland 46900
Edinburgh 21000
Glasgow 25900
Wales 42500
Bangor 12800
Cardiff 29700
==========
Total 284700
"""
