python - Organizing csv data and computing average grades -

i have sample csv data of classes , grades on 500 rows , looks this

courseid  title  teacher  avggpa  students   bs   cs    ds   fs 101       math   stevens  3.15    105      25.2 45.1 16.7  10.1 2.9 101       math   stevens  2.98    95       20.2 30.1 30.5  11.5 5.4 101       math   smith    3.33    120      33.1 40.1 10.2  7.6  4.3 103      english jane     3.55    108      20.5 16.2 16.5  20.5 10.2 103      english jane     3.47    100      25.2 38.0 22.0  7.0  2.0 202      science roberts  2.67    80       12.0 35.0 27.5  12.5 8.3 

(pretend comma separated, typed formatting purposes. percentages don't add 100% pretend do)

so far have is:

with open(filename, 'rb') f:     reader = csv.reader(f, delimiter=',')     next(reader, none)                        #to skip header     self.data = list(reader)  case_list = [] entry in self.data:     case = {'course_number': entry[1], 'course_title': entry[2], 'teacher': entry[3]... #and on each header     case_list.append(case) 

so have list of dictionaries each dictionary entry 1 row csv file.

my goal combine , average avggpa , as, bs, cs, ds, fs teachers teach same course more once. in example, average grades of steven's , jane's classes, , represent visual. if teacher teaches 1 course, represent grades visual.

i'm struggling coming method determine if teacher teaches more 1 course. along lines of looping through list , checking if courseid , teacher in dictionary, , calling function average gpas if so, can't seem think out logic.

any appreciated , if more clarification needed please let me know. if there better approach organizing csv data did, please let me know!

first of all, remember lists start indexing @ 0 line in add each entry off 1 in each field. start at

entry[0] 

anyways, you've organised list of dicts, each dict represents stats of given course. purposes, better organise information in single dict key teacher's name , course id , value total stats course. that, initialise empty dict , iterate throw rows of csv, checking if there entry in dict given teacher/courseid , updating if or adding if not. this:

stats = {} entry in self.data:     # convert type     entry[3] = float(entry[3])     entry[4] = float(entry[4])     # check if teacher in dict     if not entry[0] + entry[2] in stats:         # add new row         stats[entry[0] + entry[2]] = {'total_students':entry[4], 'weighted_gpa':entry[4]*entry[3]}     else:         # update row         stats[entry[0] + entry[2]]['weighted_gpa'] = stats[entry[0] + entry[2]]['weighted_gpa'] + entry[4]*entry[3]         stats[entry[0] + entry[2]]['total_students'] = stats[entry[0] + entry[2]]['total_students'] + entry[4] 

then can run through dictionary , average gpas:

for teachercourse in stats:     teachercourse['avg_gpa'] = teachercourse['weighted_gpa'] / teachercourse['total_students'] 

i kept average gpas readability add 'total_weighted_number_of_as' etc full list of desired stats