# scores-list.py
# David Kauchak
# 10/10/2011
#
# A set of functions for reading in scores and calculating
# various statistics from the input scores.

def get_scores():
    """Read user input of numerical scores as floats into a list
    and return the list"""
    print "Enter the scores one at a time.  Blank score finishes."
    
    scores = []
    line = raw_input("Enter score: ")
    
    while line:
        scores.append(float(line))
        line = raw_input("Enter score: ")
    
    return scores
        
def inelegant_average(scores):
    """Calculate the average of the values in list scores"""
    sum = 0.0
    count = 0
    
    for score in scores:
        sum += score
        count += 1
    
    return sum/count

def average(scores):
    """Calculate the average of the values in list scores"""
    return float(sum(scores))/len(scores)

def almost_median(scores):
    """Calculate the median of the values in list scores (almost)"""    
    scores.sort()
    
    return scores[len(scores)/2]

def assign_grades(scores):
    """Given a list of scores (numbers) calculate a letter grade
    for each score.  If the score is greater than the average
    then it receives and A.  If it is less than, an F.  The function
    returns a list of grades where index i in the list corresponds
    to the score i in the input list"""
    avg = average(scores)
    grades = []
    
    for score in scores:
        if score >= avg:
            # gets an A
            grades.append("A")
        else:
            grades.append("F")
    
    return grades

def print_class_stats(scores):
    """Print out various stats about the list of scores"""
    print "Class max: " + str(max(scores))
    print "Class min: " + str(min(scores))
    print "Class average: " + str(average(scores))
    print "Class median: " + str(almost_median(scores))
    print "Class grades:"
    
    grades = assign_grades(scores)
    
    for i in range(len(grades)):
        print str(scores[i]) + " -> " + grades[i]
    
# get the scores from the user and then print out the stats
scores = get_scores()
print "-"*10
print_class_stats(scores)