Level 1: Mortgage Loans - defining abstract classes

Programming requirements

The programming task of this level is to complete the four functions of findPayment, init, makePayment and getTotalPaid in 7-1.py file to meet the requirements of calculating mortgage loans. Specific requirements are as follows:

This pass requires to complete the four functions described above, and help people choose the appropriate way of loan by studying the rules of mortgage loan;
See the following test examples for details.
The code framework of the code file 7-1.py involved in this level is as follows:

def findPayment(loan, r, m):
#Please add code here to complete the function findPayment
#********** Begin #
#* End #
class Mortgage(object):
def init(self, loan, annRate, months):
#Please add code here to complete the function__ init__
#* Begin #
#* End #
self.legend = None
def makePayment(self):
#Please add code here to complete the function makePayment
#* Begin #
#* End #
def getTotalPaid(self):
#Please add code here to complete the function getTotalPaid
#* Begin #
#* End *********#
def str(self):
return 'The Mortgage is {self.legend}, Loan is {self.loan}, Months is {self.months}, Rate is {self.rate:.2f}, Monthly payment is {self.payment:.2f}'.format(self=self)
if name=="main":
print(Mortgage(100000, 6.5, 36))
print(Mortgage(100000, 6.5, 120))

Test description

The platform will test the code you write:

Test input: no input
Expected output:

The Mortgage is None, Loan is 100000, Months is 36, Rate is 0.01, Monthly payment is 3064.90
The Mortgage is None, Loan is 100000, Months is 120, Rate is 0.01, Monthly payment is 1135.48
Start your mission. I wish you success!

code

def findPayment(loan, r, m):
	#********** Begin *********#
    # Write the code below
    return loan*((r*pow(1+r,m)/(pow(1+r,m)-1)))
    # Please do not modify the following code
	#********** End *********#
class Mortgage(object):
    def __init__(self, loan, annRate, months):
    	#********** Begin *********#
        # Write the code below
        self.loan=loan
        self.annRate=annRate
        self.months=months
        self.rate = self.annRate/12/100
        self.paid = [0.0]
        self.owed = [loan]
        self.payment = findPayment(loan,self.rate,months)
        # Please do not modify the following code
        #********** End *********#
        self.legend = None

    def makePayment(self):
    	#********** Begin *********#
        # Write the code below
        self.paid.append(self.payment)
        reduction = self.payment - self.owed[-1] * self.rate
        self.owed.append(self.owed[-1] - reduction)
        # Please do not modify the following code
        #********** End *********#

    def getTotalPaid(self):
    	#********** Begin *********#
        # Write the code below
        return sum(self.paid)
        # Please do not modify the following code
        #********** End *********#

    def __str__(self):
        return 'The Mortgage is {self.legend}, Loan is {self.loan}, Months is {self.months}, Rate is {self.rate:.2f}, Monthly payment is {self.payment:.2f}'.format(self=self)

if __name__=="__main__":
    print(Mortgage(100000, 6.5, 36))
    print(Mortgage(100000, 6.5, 120))

Level 2: modeling of three loan methods

Programming requirements

The programming task of this pass is to complete the code of begin end interval in 7-2.py file and realize the requirements of modeling with three loan methods. Specific requirements are as follows:

It is required to complete the init function and makePayment function defined in 3 subclasses in 7-2.py file to realize the modeling function of three loan modes;
See the following test examples for details.
The code framework of the code file 7-2.py involved in this level is as follows:

def findPayment(loan, r, m):
return loan * ((r * (1 + r) ** m) / ((1 + r) ** m - 1))
class Mortgage(object):
def init(self, loan, annRate, months):
self.loan = loan
self.rate = annRate / 1200.0
self.months = months
self.paid = [0.0]
self.owed = [loan]
self.payment = findPayment(loan, self.rate, self.months)
self.legend = None
def makePayment(self):
self.paid.append(self.payment)
reduction = self.payment - self.owed[-1] * self.rate
self.owed.append(self.owed[-1] - reduction)
def getTotalPaid(self):
return sum(self.paid)
def str(self):
return str(self.legend)
class Fixed(Mortgage):
def init(self, loan, r, months):
#Please add code here to complete the function__ init__
#********** Begin #
#* End #
self.legend = 'Fixed, ' + str® + '%, for ' + str(months) + ' months'
class FixedWithPoints(Mortgage):
def init(self, loan, r, months, pts):
#Please add code here to complete the function__ init__
#* Begin #
#* End #
self.legend = 'Fixed, ' + str® + '%, ' + str(pts) + ' points, for ' + str(months) + ' months'
class TwoRate(Mortgage):
def init(self, loan, r, months, teaserRate, teaserMonths):
#Please add code here to complete the function__ init__
#* Begin #
#* End #
self.legend = str(teaserRate)
+ '% for ' + str(self.teaserMonths)
+ ' months, \n then ' + str® + '%, for ' + str(months) + ' months'
def makePayment(self):
#Please add code here to complete the function makePayment
#* Begin #
#* End *********#
Mortgage.makePayment(self)
if name=="main":
print(Fixed(100000, 6.5, 36))
print(Fixed(100000, 6.5, 120))
print(FixedWithPoints(100000, 6.5, 36, 20))
print(FixedWithPoints(100000, 6.5, 120, 20))
print(TwoRate(100000, 9.0, 36, 4.8, 12))
print(TwoRate(100000, 7.0, 120, 4.8, 36))

Test description

The platform will test the code you write:

Test input: no input
Expected output:

Fixed, 6.5%, for 36 months
Fixed, 6.5%, for 120 months
Fixed, 6.5%, 20 points, for 36 months
Fixed, 6.5%, 20 points, for 120 months
4.8% for 12 months,
then 9.0%, for 36 months
4.8% for 36 months,
then 7.0%, for 120 months
Start your mission. I wish you success!

code

def findPayment(loan, r, m):
    return loan * ((r * (1 + r) ** m) / ((1 + r) ** m - 1))

class Mortgage(object):
     def __init__(self, loan, annRate, months):
         self.loan = loan
         self.rate = annRate / 1200.0
         self.months = months
         self.paid = [0.0]
         self.owed = [loan]
         self.payment = findPayment(loan, self.rate, self.months)
         self.legend = None

     def makePayment(self):
         self.paid.append(self.payment)
         reduction = self.payment - self.owed[-1] * self.rate
         self.owed.append(self.owed[-1] - reduction)

     def getTotalPaid(self):
         return sum(self.paid)

     def __str__(self):
         return str(self.legend)


class Fixed(Mortgage):
    def __init__(self, loan, r, months):
        # Please add code here to complete the function__ init__
        #********** Begin *********#
        self.loan = loan
        self.r = r
        self.months = months
        #********** End *********#
        self.legend = 'Fixed, ' + str(r) + '%, for ' + str(months) + ' months'


class FixedWithPoints(Mortgage):
    def __init__(self, loan, r, months, pts):
        # Please add code here to complete the function__ init__
        #********** Begin *********#
        self.loan = loan
        self.r = r
        self.months = months
        self.pts=pts
        #********** End *********#
        self.legend = 'Fixed, ' + str(r) + '%, ' + str(pts) + ' points, for ' + str(months) + ' months'


class TwoRate(Mortgage):
    def __init__(self, loan, r, months, teaserRate, teaserMonths):
        # Please add code here to complete the function__ init__
        #********** Begin *********#
        self.loan = loan
        self.r = r
        self.months = months
        self.teaserRate=teaserRate
        self.teaserMonths=teaserMonths
        #********** End *********#
        self.legend = str(teaserRate)\
                      + '% for ' + str(self.teaserMonths)\
                      + ' months, \n then ' + str(r) + '%, for ' + str(months) + ' months'

    def makePayment(self):
        # Please add code here to complete the function makePayment
        #********** Begin *********#
        if len(self.paid) == self.teaserMonths + 1:
            self.rate = self.nextRate
            self.payment = findPayment(self.owed[-1], self.rate, self.months - self.teaserMonths)
        #********** End *********#
        Mortgage.makePayment(self)

if __name__=="__main__":

    print(Fixed(100000, 6.5, 36))
    print(Fixed(100000, 6.5, 120))

    print(FixedWithPoints(100000, 6.5, 36, 20))
    print(FixedWithPoints(100000, 6.5, 120, 20))

    print(TwoRate(100000, 9.0, 36, 4.8, 12))
    print(TwoRate(100000, 7.0, 120, 4.8, 36))

Level 3: compare the advantages and disadvantages of various loans

Programming requirements

The programming task of this pass is to complete the code of begin end interval in step3/7-3.py file, so as to meet the requirements of comparing the advantages and disadvantages of various loans. Specific requirements are as follows:

It is required to complete the compareMortgages function, then calculate the three loan methods respectively, and finally return the total amount to the bank. On this basis, compare the advantages and disadvantages of the three loan methods;
See the following test examples for details.
The code framework of the code file 7-3.py involved in this level is as follows:

def findPayment(loan, r, m):
return loan * ((r * (1 + r) ** m) / ((1 + r) ** m - 1))
class Mortgage(object):
def init(self, loan, annRate, months):
self.loan = loan
self.rate = annRate / 1200.0
self.months = months
self.paid = [0.0]
self.owed = [loan]
self.payment = findPayment(loan, self.rate, self.months)
self.legend = None
def makePayment(self):
self.paid.append(self.payment)
reduction = self.payment - self.owed[-1] * self.rate
self.owed.append(self.owed[-1] - reduction)
def getTotalPaid(self):
return sum(self.paid)
def str(self):
return str(self.legend)
class Fixed(Mortgage):
def init(self, loan, r, months):
Mortgage.init(self, loan, r, months)
self.legend = 'Fixed, ' + str® + '%, for ' + str(months) + ' months'
class FixedWithPoints(Mortgage):
def init(self, loan, r, months, pts):
Mortgage.init(self, loan, r, months)
self.pts = pts
self.paid = [loan * (pts / 100.0)]
self.legend = 'Fixed, ' + str® + '%, ' + str(pts) + ' points, for ' + str(months) + ' months'
class TwoRate(Mortgage):
def init(self, loan, r, months, teaserRate, teaserMonths):
Mortgage.init(self, loan, teaserRate, months)
self.teaserMonths = teaserMonths
self.teaserRate = teaserRate/1200
self.nextRate = r / 1200.0
self.legend = str(teaserRate)
+ '% for ' + str(self.teaserMonths)
+ ' months, \n then ' + str® + '%, for ' + str(months) + ' months'
def makePayment(self):
if len(self.paid) == self.teaserMonths + 1:
self.rate = self.nextRate
self.payment = findPayment(self.owed[-1], self.rate, self.months - self.teaserMonths)
Mortgage.makePayment(self)
def compareMortgages(amt, years, fixedRate, pts, ptsRate, varRate1, varRate2, varMonths):
#Please add code here to complete the function compareMortgages
#********** Begin #
#* End #
for m in range(totMonths):
#Please add code here to complete the function compareMortgages
#* Begin #
#* End ********#
for m in morts:
print(m)
print('Loan ' + str(amt) + ' Total payments = ' + str(int(m.getTotalPaid())))
if name=="main":
compareMortgages(200000, 30, 7, 3.25, 5, 4.5, 9.5, 48)
print(''40)
compareMortgages(1000000, 30, 7, 20, 5, 4.5, 9.5, 48)
print('' * 40)
compareMortgages(500000, 10, 7, 20, 5, 4.5, 9.5, 48)

Test description

The platform will test the code you write:

Test input: no input
Expected output:
Fixed, 7%, for 360 months
Loan 200000 Total payments = 479017
Fixed, 5%, 3.25 points, for 360 months
Loan 200000 Total payments = 393011
4.5% for 48 months,
then 9.5%, for 360 months
Loan 200000 Total payments = 551444

Fixed, 7%, for 360 months
Loan 1000000 Total payments = 2395088
Fixed, 5%, 20 points, for 360 months
Loan 1000000 Total payments = 2132557
4.5% for 48 months,
then 9.5%, for 360 months
Loan 1000000 Total payments = 2757224

Fixed, 7%, for 120 months
Loan 500000 Total payments = 696650
Fixed, 5%, 20 points, for 120 months
Loan 500000 Total payments = 736393
4.5% for 48 months,
then 9.5%, for 120 months
Loan 500000 Total payments = 678254

Start your mission. I wish you success!

code

def findPayment(loan, r, m):
    return loan * ((r * (1 + r) ** m) / ((1 + r) ** m - 1))

class Mortgage(object):
     def __init__(self, loan, annRate, months):
         self.loan = loan
         self.rate = annRate / 1200.0
         self.months = months
         self.paid = [0.0]
         self.owed = [loan]
         self.payment = findPayment(loan, self.rate, self.months)
         self.legend = None

     def makePayment(self):
         self.paid.append(self.payment)
         reduction = self.payment - self.owed[-1] * self.rate
         self.owed.append(self.owed[-1] - reduction)

     def getTotalPaid(self):
         return sum(self.paid)

     def __str__(self):
         return str(self.legend)


class Fixed(Mortgage):
    def __init__(self, loan, r, months):
        Mortgage.__init__(self, loan, r, months)
        self.legend = 'Fixed, ' + str(r) + '%, for ' + str(months) + ' months'


class FixedWithPoints(Mortgage):
    def __init__(self, loan, r, months, pts):
        Mortgage.__init__(self, loan, r, months)
        self.pts = pts
        self.paid = [loan * (pts / 100.0)]
        self.legend = 'Fixed, ' + str(r) + '%, ' + str(pts) + ' points, for ' + str(months) + ' months'


class TwoRate(Mortgage):
    def __init__(self, loan, r, months, teaserRate, teaserMonths):
        Mortgage.__init__(self, loan, teaserRate, months)
        self.teaserMonths = teaserMonths
        self.teaserRate = teaserRate/1200
        self.nextRate = r / 1200.0
        self.legend = str(teaserRate)\
                      + '% for ' + str(self.teaserMonths)\
                      + ' months, \n then ' + str(r) + '%, for ' + str(months) + ' months'

    def makePayment(self):
        if len(self.paid) == self.teaserMonths + 1:
            self.rate = self.nextRate
            self.payment = findPayment(self.owed[-1], self.rate, self.months - self.teaserMonths)
        Mortgage.makePayment(self)


def compareMortgages(amt, years, fixedRate, pts, ptsRate, varRate1, varRate2, varMonths):
    # Please add code here to complete the function compareMortgages
        #********** Begin *********#
    totMonths = years * 12
    fixed1 = Fixed(amt, fixedRate, totMonths)
    fixed2 = FixedWithPoints(amt, ptsRate, totMonths, pts)
    twoRate = TwoRate(amt, varRate2, totMonths, varRate1, varMonths)
    morts = [fixed1, fixed2, twoRate]
        #********** End *********#
    for m in range(totMonths):
        # Please add code here to complete the function compareMortgages
        #********** Begin *********#
        for mort in morts:
            mort.makePayment()
        #********** End *********#
    for m in morts:
        print(m)
        print('Loan ' + str(amt) + ' Total payments = ' + str(int(m.getTotalPaid())))

if __name__=="__main__":
    compareMortgages(200000, 30, 7, 3.25, 5, 4.5, 9.5, 48)
    print('*'*40)
    compareMortgages(1000000, 30, 7, 20, 5, 4.5, 9.5, 48)
    print('*' * 40)
    compareMortgages(500000, 10, 7, 20, 5, 4.5, 9.5, 48)

educoder Linux and Python Programming 2021 answer
https://blog.csdn.net/u014708644/category_11465058.html