计算累积平均值（我该怎么做？）

Question

我有三个函数，一个用于计算实验室平均值，一个用于加权分数，一个用于程序平均值。这些函数计算用户选择的特定学生的分数。 （例如。将计算实验室平均值。仅适用于 Ablao 而不是其他学生）

Ablao 3 74 96 72 88 71 80 83 77 90 88 95 71 76 94 80 74 98 77 
Anderson 3 76 92 98 95 92 76 93 97 85 76 85 93 82 88 75 84 92 77 
Aspinwall 1 86 74 78 97 86 94 73 95 74 91 75 94 83 99 83 78 88 96 
Bacon 4 72 95 81 80 89 88 100 87 87 81 79 77 75 83 87 96 72 95 

文件中有 60 名学生的信息。姓名后的第一个数字代表学生的年级。 1=大一2=大二等

我需要创建一个新函数，该函数将使用我现有的函数来计算所有学生的平均数，以及每个年级学生的平均数，然后平均这些平均数，找到最大值和最小值。

到目前为止，我为此功能编写的代码不起作用，我不知道如何着手解决这个问题。

with open(FileName, 'r') as f:
    line = f.readlines()

student_status=(float(line.split()[1]))

def make_lists_of_status():
    if (student_status==1):
        Freshman.append(student_scores)
    elif (student_status==2):
        Sophomores.append(student_scores)
    elif (student_status==3):
        Juniors.append(student_scores)
    elif (student_status==4):
        Seniors.append(student_scores)

预期的输出应该是这样的

    This  option is for viewing statistics sorted by the year of student.
    Please select one of the following options: 
    a for ALL YEARS
    b for FRESHMAN
    c for SOPHMORES
    d for JUNIORS
    e for SENIORS

Enter your choice here: e

For Seniors:
High/Low/Mean of all Weighted Scores:  89.53999999999999 /   81.60000000000001 / 86.15736842105264
High/Low/Mean of all Lab Averages:  89.6 / 80.2 / 86.21052631578948
High/Low/Mean of all Program Averages:  94.33333333333333 / 77.0 / 86.78947368421052

Answer 1

我认为这是你想要的：

scores_student = {}
scores_grade   = [[],[],[],[]]
scores_all     = []
with open("students.txt", "r") as f:
    for line in f:
        # Parse the line
        toks   = line.split()
        name   = toks[0]
        grade  = int(toks[1])
        scores = [float(tok) for tok in toks[2:]]
        # Save scores both per student, in that student's grade, and total
        scores_student[(name,grade)] = scores
        scores_grade[grade-1] += scores
        scores_all += scores

# Print individual student info
print "Students"
for name,grade in sorted(scores_student):
    score = scores_student[(name,grade)]
    print "%-10s %d mean %4.1f max %3d min %3d" % (name, grade, sum(score)/len(score), max(score), min(score))
print
print "Summary"
for grade, score in enumerate(scores_grade):
    if len(score) > 0:
        print "grade %d mean %4.1f max %3d min %3d" % (grade+1, sum(score)/len(score), max(score), min(score))
print "all     mean %4.1f max %3d min %3d" % (sum(scores_all)/len(scores_all), max(scores_all), min(scores_all))

Answer 2

这可以通过字典来完成。

students = {}

with open("inCSV.txt", "r") as f:
    for line in f.readlines():
        data = line.rstrip().split(" ")

        student_name = data[0]
        student_grade = data[1]
        student_data = [int(x) for x in data[2:]]
        student_avg = sum(student_data[2:])/float(len(student_data[2:]))

        # Set the students name to a tuple of student's grade and average
        students[student_name] = (student_grade, student_avg)

# Sort the students by their averages. (Descending order)
# Add reverse=True to have it in ascending order
print sorted(students.keys(), key=lambda x: students[x][1])

编辑

它仍然可以以类似的方式完成。

students = {}

def weighted_scores(x):
    return x

with open("inCSV.txt", "r") as f:
    for line in f.readlines():
        data = line.rstrip().split(" ")

        student_name = data[0]
        student_grade = data[1]
        student_data = [int(x) for x in data[2:]]

        student_program_avg = sum(student_data[2:])/float(len(student_data[2:]))
        # Edit this part to your code
        student_weighted_scores = weighted_scores(data[2:])
        student_lab_averages = lab_average(data[2:])

        students[student_name] = (student_grade,
                                  student_weighted_scores,
                                  student_lab_averages,
                                  student_program_avg)
print students

def get_level(x):
    ret_dict = {}
    for k, v in students:
        if v[0] == x:
            ret_dict[k] = v


def choose(x):
    people = get_level(x)
    overall = []

    for s in range(1, 4):
        # Get grades of either weighted scores, lab averages or just average.
        # Sort grades in descending order
        grades = sorted(people.keys(), key=lambda x: people[x][s])

        highest = grades[0]
        lowest = grades[-1]
        mean = sum(grades[2:])/float(len(grades[2:])

        overall.append((highest, lowest, mean))

    # overall[0] => weighted scores
    # overall[1] => lab averages
    # overall[2] => program average
    # overall[x][0] => highest of x
    # overall[x][1] => lowest of x
    # overall[x][2] => mean of x

    print "For %i level:" % (x)
    print "High/Low/Mean of Weighted Scores: %i / %i / %i" % (overall[0][0], overall[0][1], overall[0][2])
    print "High/Low/Mean of Lab Averages: %i / %i / %i" % (overall[1][0], overall[1][1], overall[1][2])
    print "High/Low/Mean of Weighted Scores: %i / %i / %i" % (overall[2][0], overall[2][1], overall[2][2])

# Let's say you picked seniors:
choose(4)