# Dahv Reinhart - V00735279

# SEng265 - Assignment 3

# 'Quiz Time' - Computes the average time taken on each question in a quiz accross all students. (measure of difficulty)

# Due Nov 28th, 2015

import libxml2

import sys

import quiz_library

'''

purpose

Accept 1 or more log file names on the command line.

For each log file, compute the total time taken for each question.

Write to standard output, the average time spent for each question.

preconditions

Each command-line argument is the name of a readable and

legal quiz log file.

All the log_files have the same number of questions.

'''

# handle command line arguments

if len(sys.argv) < 2:

print 'Syntax:', sys.argv[0], 'quiz_log_file ...' #must have legal arguments supplied on the command line

sys.exit()

initQ = quiz_library.load_quiz_log(sys.argv[1]) #since it is guarenteed that each log_file will have the same number

q = quiz_library.compute_question_count(initQ) #of questions, initialize the question counter to the fist file.

for y in range(0, q): #goes through each question in the log files

time = []

for x in range(1, len(sys.argv)): #for each question, goes through all the log_files

difference = [0, 0]

log_list = quiz_library.load_quiz_log(sys.argv[x])

for z in log_list:

if int(z.index) == y and isinstance(z, quiz_library.Display): #the first 'Display' object

if difference[0] == 0: #of a given question

difference[0] = z.time #time 1

elif int(z.index) == (y+1) and isinstance(z, quiz_library.Display): #the 'Display' objct of

if difference[1] == 0: #the next question

difference[1] = z.time #time 2

break #dont want to keep going if we already have time 1 and 2

elif log_list[len(log_list) -1] == z: #if we are at the end of the log_list (the last question),

difference[1] = z.time #then set time 2 equal to the final answer element since

#there is no upcoming 'Display' object coming

if difference[0] == 0 and y != 0: #if the question was never encounterd, do not include it in

difference[1] = 0 #the time calculation.

questionTime = (int(difference[1]) - int(difference[0])) #time taken on a question in 1 log_file

time.append(questionTime) #make a list of times for a question accross all log_files

totalTime = float(reduce(lambda x,y: x+y , time)) #add the times for a given question

averageTime = (totalTime / (len(sys.argv) - 1)) #divide the total time by the number of log_files

#i.e. the number of occurances of each question

separate = ','

if y == (q-1):

separate = '' #fence-post printing

sys.stdout.write((str(averageTime) + separate))

print ''