summing up a column in a csv file based on user search - python-2.7

Question

I have the following csv file:
data.cvs
school,students,teachers,subs
us-school1,10,2,0
us-school2,20,4,2
uk-school1,10,2,0
de-school1,10,3,1
de-school1,15,3,3
I am trying to have a user search for the school country (us or uk, or de)
and then sum up the corresponding column. (e.g. sum all students in us-* etc.)
So far i am able to search using the raw_input and display column contents corresponding to the country, appreciate if someone can give me some pointers on how i can achive this.
desired output:
Country: us
Total students: 30
Total teachers: 6
Total subs: 2
--
import csv
import re
search = raw_input('Enter school (e.g. us: ')
with open('data.csv') as csvfile:
reader = csv.DictReader(csvfile)
for row in reader:
school = row['school']
students = row['students']
teachers = row['teachers']
sub = row['subs']
if re.match(search, schools) is not None:
print students

Answer 1

That's relatively easy to do - all you need is a dict to hold group your countries, and then just add together all of the values:
import collections
import csv
result = {} # store the results
with open("data.csv", "rb") as f: # open our file
reader = csv.DictReader(f) # use csv.DictReader for convenience
for row in reader:
country = row.pop("school")[:2] # get our country
result[country] = result.get(country, collections.defaultdict(int)) # country group
for column in row: # loop through all other columns
result[country][column] += int(row[column]) # add them together
# Now you can use or print your result by country:
for country in result:
print("Country: {}".format(country))
print("Total students: {}".format(result[country].get("students", 0)))
print("Total teachers: {}".format(result[country].get("teachers", 0)))
print("Total subs: {}\n".format(result[country].get("subs", 0)))
This is also universal as you can add additional number columns (e.g. janitors :D) and it will happily sum them together, but keep in mind that it works only with integers (if you want floats, replace the references to int with float) and it expects that every field except school is a number.

Answer 2

Your problem could be solved with something like this:
import csv
search = raw_input('Enter school (e.g. us: ')
with open('data.csv') as csvfile:
reader = csv.DictReader(csvfile)
result_countrys = {}
for row in reader:
students = int(row['students'])
teachers = int(row['teachers'])
subs = int(row['subs'])
subs = row['subs']
country = school[: 2]
if country in result_countrys:
count = result_countrys[country]
count['students'] = count['students'] + students
count['teachers'] = count['teachers'] + teachers
count['subs'] = count['subs'] + subs
else :
dic = {}
dic['students'] = students
dic['teachers'] = teachers
dic['subs'] = subs
result_countrys[country] = dic
for k, v in result_countrys[search].iteritems():
print("country " + str(search) + " has " + str(v) + " " + str(k))
I tryed out with this set of values:
reader = [{'school': 'us-school1', 'students': 20, 'teachers': 6, 'subs': 2}, {'school': 'us-school2', 'students': 20, 'teachers': 6, 'subs': 2}, {'school': 'uk-school1', 'students': 20, 'teachers': 6, 'subs': 2}]
and the result is:
Enter school (e.g. us): us
country us has 30 students
country us has 6 teachers
country us has 2 subs