[Tutor] Strange list behaviour in classes

[ALAN GAULD]

One point:

class Statistics:
def __init__(self, *value_list):
>self.value = value_list
>self.square_list= []
>def mean(self, *value_list):
>try :
>ave = sum(self.value) / len(self.value)
>except ZeroDivisionError:
>ave = 0
>return ave
You don't use value_list here you use self.value. So you don't need value_list

def median(self, *value_list):
>if len(self.value) <= 2:
>n = self.mean(self.value)
>elif len(self.value) % 2 == 1:
>m = (len(self.value) - 1)/2
>n = self.value[m+1]
>else:
>m = len(self.value) / 2
>m = int(m)
>n = (self.value[m-1] + self.value[m]) / 2
>return n
Same here...
 
def variance(self, *value_list):
>average = self.mean(*self.value)
>for n in range(len(self.value)):
>square = (self.value[n] - average)**2
>self.square_list.append(square)
>try:
>var = sum(self.square_list) / len(self.square_list)
>except ZeroDivisionError:
>var = 0
>return var
And here...

def stdev(self, *value_list):
>var = self.variance(*self.value)
>sdev = var**(1/2)
>return sdev
And here... 
def zscore(self, x, *value_list):
>average = self.mean(self.value)
>sdev = self.stdev(self.value)
>try:
>z = (x - average) / sdev
>except ZeroDivisionError:
>z = 0
>return z
And here....

a = [1,2,3,4,5,6,7,8,9,10]
>stats = Statistics(*a)
>So you need the *a here


mean = stats.mean(*a)
>median = stats.median(*a)
>var = stats.variance(*a)
>stdev = stats.stdev(*a)
>z = stats.zscore(5, *a)
>But you don't need to pass in *a in any of these calls.
Its already stored in the object.

Also instead of returning these values (or as well as)
you could have stored them as variables inside the 
object.


print(mean, median, var, stdev, z)
>
>In which case this would become

print(self.theMean,self.theMedian, etc...)

Just an alternative for consideration.

Alan G.
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