USE! PYTHON!!! Problems: Use the usual naming scheme. Make sure you include the

Question

USE! PYTHON!!!

Problems:

Use the usual naming scheme. Make sure you include the name(s) of any collaborators, and the results of running the doctest on your solutions.

1. Implement a container class Stat that stores a sequence of numbers and provides statistical information about the numbers. It supports an overloaded constructor that initializes the container either using a list or with no parameter which creates an empty sequence. The class also includes the methods necessary to provide the following behaviors:

>>> s = Stat()

>>> s.add(2.5)

>>> s.add(4.7)

>>> s.add(78.2)

>>> s

Stat([2.5, 4.7, 78.2])

>>> len(s)

3

>>> s.min()

2.5

>>> s.max()

78.2

>>> s.sum()

85.4

>>> s.mean()

28.46666666666667

>>> s.clear()

>>> s

Stat([])

If a Stat is empty, several (but not all) methods raise errors. Note that you won’t literally see “…”.   You will instead see more information on the error.

>>> s = Stat()

>>>

>>> len(s)

0

>>> s.min()

Traceback (most recent call last):

...

EmptyStatError: empty Stat does not have a min

>>> s.max()

Traceback (most recent call last):

...

hw3.EmptyStatError: empty Stat does not have a max

>>> s.mean()

Traceback (most recent call last):

...

hw3.EmptyStatError: empty Stat does not have a mean

>>> s.sum()

0

2. Implement a class intlist which a list that stores only integers. You MUST subclass list.   Please note the following:

constructor –can be passed a list of ints, or, by default constructs an empty intlist.

< >, insert,extend – can also be used to add ints to an intlist. If you don’t know how extend works for a list, look it up.   All should raise errors if a non-int is added.

< > - can be used for item assignment using an index. Raises error if non-int is used.

< > – write a method odds() which returns an intlist consisting of the odd int’s.   They should not be removed from the original.

< > – same as odds(), but for even ints

< > – also write an Exception class NotIntError that subclasses Exception.

< > – a NonIntError should be raised when client code attempts to place something other than an int in an intlist. This can happen in three ways (all shown in code below):

< >

< >

The constructor – when passed a list that contains something other an int

Note: you can check whether item is an int by evaluating the expression type(item)==int

Your goal is to get the following behavior:

>>> il = intlist()

>>> il

intlist([])

>>> il = intlist([1,2,3])

>>> il

intlist([1, 2, 3])

>>> il.append( 5 )

>>> il

intlist([1, 2, 3, 5])

>>> il.insert(1,99)

>>> il

intlist([1, 99, 2, 3, 5])

>>> il.extend( [22,44,66] )

>>> il

intlist([1, 99, 2, 3, 5, 22, 44, 66])

>>> odds = il.odds()

>>> odds

intlist([1, 99, 3, 5])

>>> evens = il.evens()

>>> evens

intlist([2, 22, 44, 66])

>>> il

intlist([1, 99, 2, 3, 5, 22, 44, 66])

>>> il[2] = -12   # calls __setitem__

>>> il

intlist([1, 99, -12, 3, 5, 22, 44, 66])

>>> il[4]   # calls __getitem__

5

Trying to put anything except for an int into an intlist will always raise an NotIntError. Note that there 5 different ways this could be attempted:

>>> il.append(33.4)

Traceback (most recent call last):

...

NotIntError: 33.4 not an int

>>> il.insert(2,True)

Traceback (most recent call last):

...

NotIntError: True not an int

>>> il = intlist([2,3,4,"apple"])

Traceback (most recent call last):

...

NotIntError: apple not an int

>>> il.extend( [2,3,'hello'])

Traceback (most recent call last):

...

NotIntError: hello not an int

>>> il[2] = 22.3

Traceback (most recent call last):

...

NotIntError: 22.3 not an int

Explanation / Answer

Good Wishes,

Program 1:

class Stat(object):

def __init__(self,seq1= None):

if seq1 is None:

self.seq=set()

else :

self.seq=seq1

def add(self,a):

try

self.seq.add(a)

except:

print("stat empty")

def min(self):

try:

print min(self.seq)

except:

print ("empty stat does not have a min")

def max(self):

try:

print max(self.seq)

except:

print("empty stat dose not have max")

def sum(self):

try:

print sum(self.seq)

except:

print("no sum stat empty")

def mean(self):

try:

l=len(self.seq)

s=sum(self.seq)

print (s/l)

except:

print("empty stat has no mean")

def clear(self):

try:

print self.seq.clear()

except:

print("no clear stat empty")

S1=Stat()

S2=Stat({1,2,3})

S1.add(23)

S2.add(23)

print S1.seq

print S2.seq

print len(S2.seq)

S2.min()

S2.max()

S2.sum()

S2.mean()

S2.clear()

print S2.seq

print len(S2.seq)

S2.min()

S2.max()

S2.sum()

S2.mean()

S2.clear()

Program 2:

class intlist(object):

def __init__(self,l=None):

if l is None:

self.il=[]

else:

self.il=l

def append(self,a):

self.il.append(a)

print self.il

def extend(self,a):

self.il.extend(a)

print self.il

def insert(self,index,a):

self.il.insert(index,a)

print self.il

def odds(self):

c=[]

for l in self.il:

if(l%2!=0):

c.append(l)

print c

def evens(self):

c=[]

for l in self.il:

if(l%2==0):

c.append(l)

print c

ilist=intlist()

ilist.append(4)

ilist.extend([5,7,3])

ilist.insert(2,9)

ilist.odds()

ilist.evens()

As per the time alloted to me I did the first question completely but in the second question I did with the code to do all the operations mentioned but the exception handling was not included

just include the below part in your code:

class NotIntError(Exception):
   def __init__(self, arg):
      self.args = arg

and then include try except block in all the methods of the class

try:

# test each element in list anf if not an integer then raise an exception as follows
   raise NotIntError(i+" is not an integer")

# if element is integer then exceute the code here
except NotIntError,e:
   print e.args

Hope this is clear.

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