Files
edx-platform/djangoapps/courseware/grades.py

456 lines
20 KiB
Python

import courseware.content_parser as content_parser
import courseware.modules
import logging
import random
import urllib
from collections import namedtuple
from django.conf import settings
from lxml import etree
from models import StudentModule
from student.models import UserProfile
log = logging.getLogger("mitx.courseware")
Score = namedtuple("Score", "earned possible graded section")
SectionPercentage = namedtuple("SectionPercentage", "percentage label summary")
class CourseGrader:
def grade(self, grade_sheet):
raise NotImplementedError
class SingleSectionGrader(CourseGrader):
"""
This grades a single section with the format section_format and the name section_name.
"""
def __init__(self, section_format, section_name, label = None, category = None):
self.section_format = section_format
self.section_name = section_name
self.label = label or section_name
self.category = category or section_name
def grade(self, grade_sheet):
foundScore = None
if self.section_format in grade_sheet:
for score in grade_sheet[self.section_format]:
if score.section == self.section_name:
foundScore = score
break
if foundScore:
percent = foundScore.earned / float(foundScore.possible)
detail = "{name} - {percent:.0%} ({earned:g}/{possible:g})".format( name = self.section_name,
percent = percent,
earned = foundScore.earned,
possible = foundScore.possible)
else:
percent = 0.0
detail = "{name} - 0% (?/?)".format(name = self.section_name)
breakdown = [{'percent': percent, 'label': self.label, 'detail': detail, 'category': self.category, 'prominent': True}]
return {'percent' : percent,
'section_breakdown' : breakdown,
#No grade_breakdown here
}
class AssignmentFormatGrader(CourseGrader):
"""
Grades all sections specified in course_format with an equal weight. A specified
number of lowest scores can be dropped from the calculation. The minimum number of
sections in this format must be specified (even if those sections haven't been
written yet).
category should be presentable to the user, but may not appear. When the grade breakdown is
displayed, scores from the same category will be similar (for example, by color).
section_detail_formatter is a format string with the parameters (index, name, percent, earned, possible).
ex: "Homework {index} - {name} - {percent:.0%} ({earned:g}/{possible:g})"
section_missing_detail_formatter is a format string with the parameters (index) for
when the minimum number of sections weren't found in the course.
ex: "Unreleased Homework {index} - 0% (?/?)"
section_label_formatter is a format string for a short label with the parameters (index).
These look best when fixed-length.
ex: "HW {index:02d}"
total_detail_formatter is a format string for displaying the average score with the
parameters (percent).
ex: "Homework Average = {percent:.0%}"
total_label_formatter is a string (with no parameters).
ex: "HW Avg"
"""
def __init__(self, course_format, min_number, drop_count, category, section_detail_formatter, section_missing_detail_formatter,
section_label_formatter, total_detail_formatter, total_label_formatter):
self.course_format = course_format
self.min_number = min_number
self.drop_count = drop_count
self.category = category
self.section_detail_formatter = section_detail_formatter
self.section_missing_detail_formatter = section_missing_detail_formatter
self.section_label_formatter = section_label_formatter
self.total_detail_formatter = total_detail_formatter
self.total_label_formatter = total_label_formatter
def grade(self, grade_sheet):
def totalWithDrops(breakdown, drop_count):
#create an array of tuples with (index, mark), sorted by mark['percent'] descending
sorted_breakdown = sorted( enumerate(breakdown), key=lambda x: -x[1]['percent'] )
# A list of the indices of the dropped scores
dropped_indices = [x[0] for x in sorted_breakdown[-drop_count:]]
aggregate_score = 0
for index, mark in enumerate(breakdown):
if index not in dropped_indices:
aggregate_score += mark['percent']
aggregate_score /= len(scores) - drop_count
return aggregate_score, dropped_indices
#Figure the homework scores
scores = grade_sheet.get(self.course_format, [])
breakdown = []
for i in range(12):
if i < len(scores):
percentage = scores[i].earned / float(scores[i].possible)
summary = self.section_detail_formatter.format(index = i+1,
name = scores[i].section,
percent = percentage,
earned = scores[i].earned,
possible = scores[i].possible )
else:
percentage = 0
summary = self.section_missing_detail_formatter.format(index = i+1)
if settings.GENERATE_PROFILE_SCORES:
points_possible = random.randrange(10, 50)
points_earned = random.randrange(5, points_possible)
percentage = points_earned / float(points_possible)
summary = self.section_detail_formatter.format(index = i+1,
name = "Randomly Generated",
percent = percentage,
earned = points_earned,
possible = points_possible )
label = self.section_label_formatter.format(index = i+1)
breakdown.append( {'percent': percentage, 'label': label, 'detail': summary, 'category': self.category} )
total_percent, dropped_indices = totalWithDrops(breakdown, self.drop_count)
for dropped_index in dropped_indices:
breakdown[dropped_index]['mark'] = {'detail': "The lowest {0} scores are dropped.".format(self.drop_count) }
total_detail = self.total_detail_formatter.format(percent = total_percent)
breakdown.append( {'percent': total_percent, 'label': self.total_label_formatter, 'detail': total_detail, 'category': self.category, 'prominent': True} )
return {'percent' : total_percent,
'section_breakdown' : breakdown,
#No grade_breakdown here
}
class WeightedSubsectionsGrader(CourseGrader):
"""
This grader takes a list of tuples containing (grader, section_name, weight) and computes
a final grade by totalling the contribution of each sub grader and weighting it
accordingly. For example, the sections may be
[ (homeworkGrader, "Homework", 0.15), (labGrader, "Labs", 0.15), (midtermGrader, "Midterm", 0.30), (finalGrader, "Final", 0.40) ]
"""
def __init__(self, sections):
self.sections = sections
def grade(self, grade_sheet):
total_percent = 0.0
section_breakdown = []
grade_breakdown = []
for subgrader, section_name, weight in self.sections:
subgrade_result = subgrader.grade(grade_sheet)
weightedPercent = subgrade_result['percent'] * weight
section_detail = "{0} = {1:.1%} of a possible {2:.0%}".format(section_name, weightedPercent, weight)
total_percent += weightedPercent
section_breakdown += subgrade_result['section_breakdown']
grade_breakdown.append( {'percent' : weightedPercent, 'detail' : section_detail, 'category' : section_name} )
return {'percent' : total_percent,
'section_breakdown' : section_breakdown,
'grade_breakdown' : grade_breakdown}
def get_score(user, problem, cache):
## HACK: assumes max score is fixed per problem
id = problem.get('id')
correct = 0
# If the ID is not in the cache, add the item
if id not in cache:
module = StudentModule(module_type = 'problem', # TODO: Move into StudentModule.__init__?
module_id = id,
student = user,
state = None,
grade = 0,
max_grade = None,
done = 'i')
cache[id] = module
# Grab the # correct from cache
if id in cache:
response = cache[id]
if response.grade!=None:
correct=response.grade
# Grab max grade from cache, or if it doesn't exist, compute and save to DB
if id in cache and response.max_grade != None:
total = response.max_grade
else:
total=courseware.modules.capa_module.Module(etree.tostring(problem), "id").max_score()
response.max_grade = total
response.save()
return (correct, total)
def grade_sheet(student):
"""
This pulls a summary of all problems in the course. It returns a dictionary with two datastructures:
- courseware_summary is a summary of all sections with problems in the course. It is organized as an array of chapters,
each containing an array of sections, each containing an array of scores. This contains information for graded and ungraded
problems, and is good for displaying a course summary with due dates, etc.
- grade_summary is a summary of how the final grade breaks down. It is an array of "sections". Each section can either be
a conglomerate of scores (like labs or homeworks) which has subscores and a totalscore, or a section can be all from one assignment
(such as a midterm or final) and only has a totalscore. Each section has a weight that shows how it contributes to the total grade.
"""
dom=content_parser.course_file(student)
course = dom.xpath('//course/@name')[0]
xmlChapters = dom.xpath('//course[@name=$course]/chapter', course=course)
responses=StudentModule.objects.filter(student=student)
response_by_id = {}
for response in responses:
response_by_id[response.module_id] = response
totaled_scores = {}
chapters=[]
for c in xmlChapters:
sections = []
chname=c.get('name')
for s in dom.xpath('//course[@name=$course]/chapter[@name=$chname]/section',
course=course, chname=chname):
problems=dom.xpath('//course[@name=$course]/chapter[@name=$chname]/section[@name=$section]//problem',
course=course, chname=chname, section=s.get('name'))
graded = True if s.get('graded') == "true" else False
scores=[]
if len(problems)>0:
for p in problems:
(correct,total) = get_score(student, p, response_by_id)
# id = p.get('id')
# correct = 0
# if id in response_by_id:
# response = response_by_id[id]
# if response.grade!=None:
# correct=response.grade
# total=courseware.modules.capa_module.Module(etree.tostring(p), "id").max_score() # TODO: Add state. Not useful now, but maybe someday problems will have randomized max scores?
# print correct, total
if settings.GENERATE_PROFILE_SCORES:
if total > 1:
correct = random.randrange( max(total-2, 1) , total + 1 )
else:
correct = total
scores.append( Score(int(correct),total, graded, s.get("name")) )
section_total = Score(sum([score.earned for score in scores]),
sum([score.possible for score in scores]),
False,
s.get("name"))
graded_total = Score(sum([score.earned for score in scores if score.graded]),
sum([score.possible for score in scores if score.graded]),
True,
s.get("name"))
#Add the graded total to totaled_scores
format = s.get('format') if s.get('format') else ""
subtitle = s.get('subtitle') if s.get('subtitle') else format
if format and graded_total[1] > 0:
format_scores = totaled_scores.get(format, [])
format_scores.append( graded_total )
totaled_scores[ format ] = format_scores
section_score={'section':s.get("name"),
'scores':scores,
'section_total' : section_total,
'format' : format,
'subtitle' : subtitle,
'due' : s.get("due") or "",
'graded' : graded,
}
sections.append(section_score)
chapters.append({'course':course,
'chapter' : c.get("name"),
'sections' : sections,})
hwGrader = AssignmentFormatGrader("Homework", 12, 2, "Homework", "Homework {index} - {name} - {percent:.0%} ({earned:g}/{possible:g})",
"Unreleased Homework {index} - 0% (?/?)", "HW {index:02d}", "Homework Average = {percent:.0%}", "HW Avg")
labGrader = AssignmentFormatGrader("Lab", 12, 2, "Labs", "Lab {index} - {name} - {percent:.0%} ({earned:g}/{possible:g})",
"Unreleased Lab {index} - 0% (?/?)", "Lab {index:02d}", "Lab Average = {percent:.0%}", "Lab Avg")
midtermGrader = SingleSectionGrader("Examination", "Midterm Exam", "Midterm")
finalGrader = SingleSectionGrader("Examination", "Final Exam", "Final")
grader = WeightedSubsectionsGrader( [(hwGrader, hwGrader.category, 0.15), (labGrader, labGrader.category, 0.15),
(midtermGrader, midtermGrader.category, 0.30), (finalGrader, finalGrader.category, 0.40)] )
grade_summary = grader.grade(totaled_scores)
return {'courseware_summary' : chapters,
'grade_summary' : grade_summary}
def grade_summary_6002x(totaled_scores):
"""
This function takes the a dictionary of (graded) section scores, and applies the course grading rules to create
the grade_summary. For 6.002x this means homeworks and labs all have equal weight, with the lowest 2 of each
being dropped. There is one midterm and one final.
"""
def totalWithDrops(scores, drop_count):
#Note that this key will sort the list descending
sorted_scores = sorted( enumerate(scores), key=lambda x: -x[1].percentage )
# A list of the indices of the dropped scores
dropped_indices = [score[0] for score in sorted_scores[-drop_count:]]
aggregate_score = 0
for index, score in enumerate(scores):
if index not in dropped_indices:
aggregate_score += score.percentage
aggregate_score /= len(scores) - drop_count
return aggregate_score, dropped_indices
#Figure the homework scores
homework_scores = totaled_scores['Homework'] if 'Homework' in totaled_scores else []
homework_percentages = []
for i in range(12):
if i < len(homework_scores):
percentage = homework_scores[i].earned / float(homework_scores[i].possible)
summary = "Homework {0} - {1} - {2:.0%} ({3:g}/{4:g})".format( i + 1, homework_scores[i].section , percentage, homework_scores[i].earned, homework_scores[i].possible )
else:
percentage = 0
summary = "Unreleased Homework {0} - 0% (?/?)".format(i + 1)
if settings.GENERATE_PROFILE_SCORES:
points_possible = random.randrange(10, 50)
points_earned = random.randrange(5, points_possible)
percentage = points_earned / float(points_possible)
summary = "Random Homework - {0:.0%} ({1:g}/{2:g})".format( percentage, points_earned, points_possible )
label = "HW {0:02d}".format(i + 1)
homework_percentages.append(SectionPercentage(percentage, label, summary) )
homework_total, homework_dropped_indices = totalWithDrops(homework_percentages, 2)
#Figure the lab scores
lab_scores = totaled_scores['Lab'] if 'Lab' in totaled_scores else []
lab_percentages = []
for i in range(12):
if i < len(lab_scores):
percentage = lab_scores[i].earned / float(lab_scores[i].possible)
summary = "Lab {0} - {1} - {2:.0%} ({3:g}/{4:g})".format( i + 1, lab_scores[i].section , percentage, lab_scores[i].earned, lab_scores[i].possible )
else:
percentage = 0
summary = "Unreleased Lab {0} - 0% (?/?)".format(i + 1)
if settings.GENERATE_PROFILE_SCORES:
points_possible = random.randrange(10, 50)
points_earned = random.randrange(5, points_possible)
percentage = points_earned / float(points_possible)
summary = "Random Lab - {0:.0%} ({1:g}/{2:g})".format( percentage, points_earned, points_possible )
label = "Lab {0:02d}".format(i + 1)
lab_percentages.append(SectionPercentage(percentage, label, summary) )
lab_total, lab_dropped_indices = totalWithDrops(lab_percentages, 2)
#TODO: Pull this data about the midterm and final from the databse. It should be exactly similar to above, but we aren't sure how exams will be done yet.
midterm_score = Score('?', '?', True, "?")
midterm_percentage = 0
final_score = Score('?', '?', True, "?")
final_percentage = 0
if settings.GENERATE_PROFILE_SCORES:
midterm_score = Score(random.randrange(50, 150), 150, True, "?")
midterm_percentage = midterm_score.earned / float(midterm_score.possible)
final_score = Score(random.randrange(100, 300), 300, True, "?")
final_percentage = final_score.earned / float(final_score.possible)
grade_summary = [
{
'category': 'Homework',
'subscores' : homework_percentages,
'dropped_indices' : homework_dropped_indices,
'totalscore' : homework_total,
'totalscore_summary' : "Homework Average - {0:.0%}".format(homework_total),
'totallabel' : 'HW Avg',
'weight' : 0.15,
},
{
'category': 'Labs',
'subscores' : lab_percentages,
'dropped_indices' : lab_dropped_indices,
'totalscore' : lab_total,
'totalscore_summary' : "Lab Average - {0:.0%}".format(lab_total),
'totallabel' : 'Lab Avg',
'weight' : 0.15,
},
{
'category': 'Midterm',
'totalscore' : midterm_percentage,
'totalscore_summary' : "Midterm - {0:.0%} ({1}/{2})".format(midterm_percentage, midterm_score.earned, midterm_score.possible),
'totallabel' : 'Midterm',
'weight' : 0.30,
},
{
'category': 'Final',
'totalscore' : final_percentage,
'totalscore_summary' : "Final - {0:.0%} ({1}/{2})".format(final_percentage, final_score.earned, final_score.possible),
'totallabel' : 'Final',
'weight' : 0.40,
}
]
return grade_summary