Bisection search in Python cant find the answer? Why does it result in negative balance?
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This code get down to -73535 and exits the loop. I can't figure out what's wrong.
balance = 999999
annualInterestRate = 0.18
epsilon = 0.05
monthlyInterestRate = annualInterestRate / 12
lowerBound = balance / 12
upperBound = (balance * ((1 + monthlyInterestRate)**12)) / 12.0
print(upperBound, lowerBound)
currentBalance = balance
middle = (upperBound + lowerBound) / 2
while abs(round(upperBound - lowerBound,2)) >= epsilon:
currentBalance = balance
for i in range(12):
unpaidBalance = currentBalance - middle
currentBalance= unpaidBalance - (monthlyInterestRate * unpaidBalance)
print(currentBalance)
if abs(unpaidBalance) < 0.05:
print("hahaha")
break
elif currentBalance < 0:
upperBound = middle
elif currentBalance > 0:
lowerBound = middle
middle = (upperBound + lowerBound) / 2
python payment bisection
edited Nov 7 at 19:36
halfer
14.2k757105
asked Nov 7 at 8:33
Debora
41
add a comment |
up vote
0
down vote
favorite
This code get down to -73535 and exits the loop. I can't figure out what's wrong.
balance = 999999
annualInterestRate = 0.18
epsilon = 0.05
monthlyInterestRate = annualInterestRate / 12
lowerBound = balance / 12
upperBound = (balance * ((1 + monthlyInterestRate)**12)) / 12.0
print(upperBound, lowerBound)
currentBalance = balance
middle = (upperBound + lowerBound) / 2
while abs(round(upperBound - lowerBound,2)) >= epsilon:
currentBalance = balance
for i in range(12):
unpaidBalance = currentBalance - middle
currentBalance= unpaidBalance - (monthlyInterestRate * unpaidBalance)
print(currentBalance)
if abs(unpaidBalance) < 0.05:
print("hahaha")
break
elif currentBalance < 0:
upperBound = middle
elif currentBalance > 0:
lowerBound = middle
middle = (upperBound + lowerBound) / 2
python payment bisection
edited Nov 7 at 19:36
halfer
14.2k757105
asked Nov 7 at 8:33
Debora
41
2
In future, I would recommend following the PEP8 Style Guide as it is much more readable. Specifically, take a look at Naming conventions and whitespace in expressions and statements.
– Modelmat
Nov 7 at 8:44
Can you explain the meaning of the value you are apparently trying to converge, perhaps with a reference to the algorithm?
– tripleee
Nov 7 at 10:19
This is to try to figure out the minimum lowest payment I need to pay every month to pay off my credit card debt.I have to use bisection search.
– Debora
Nov 8 at 5:49
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
This code get down to -73535 and exits the loop. I can't figure out what's wrong.
balance = 999999
annualInterestRate = 0.18
epsilon = 0.05
monthlyInterestRate = annualInterestRate / 12
lowerBound = balance / 12
upperBound = (balance * ((1 + monthlyInterestRate)**12)) / 12.0
print(upperBound, lowerBound)
currentBalance = balance
middle = (upperBound + lowerBound) / 2
while abs(round(upperBound - lowerBound,2)) >= epsilon:
currentBalance = balance
for i in range(12):
unpaidBalance = currentBalance - middle
currentBalance= unpaidBalance - (monthlyInterestRate * unpaidBalance)
print(currentBalance)
if abs(unpaidBalance) < 0.05:
print("hahaha")
break
elif currentBalance < 0:
upperBound = middle
elif currentBalance > 0:
lowerBound = middle
middle = (upperBound + lowerBound) / 2
python payment bisection
edited Nov 7 at 19:36
halfer
14.2k757105
asked Nov 7 at 8:33
Debora
41
This code get down to -73535 and exits the loop. I can't figure out what's wrong.
balance = 999999
annualInterestRate = 0.18
epsilon = 0.05
monthlyInterestRate = annualInterestRate / 12
lowerBound = balance / 12
upperBound = (balance * ((1 + monthlyInterestRate)**12)) / 12.0
print(upperBound, lowerBound)
currentBalance = balance
middle = (upperBound + lowerBound) / 2
while abs(round(upperBound - lowerBound,2)) >= epsilon:
currentBalance = balance
for i in range(12):
unpaidBalance = currentBalance - middle
currentBalance= unpaidBalance - (monthlyInterestRate * unpaidBalance)
print(currentBalance)
if abs(unpaidBalance) < 0.05:
print("hahaha")
break
elif currentBalance < 0:
upperBound = middle
elif currentBalance > 0:
lowerBound = middle
middle = (upperBound + lowerBound) / 2
python payment bisection
python payment bisection
edited Nov 7 at 19:36
halfer
14.2k757105
asked Nov 7 at 8:33
Debora
41
edited Nov 7 at 19:36
halfer
14.2k757105
asked Nov 7 at 8:33
Debora
41
edited Nov 7 at 19:36
halfer
14.2k757105
edited Nov 7 at 19:36
halfer
14.2k757105
edited Nov 7 at 19:36
halfer
14.2k757105
14.2k757105
asked Nov 7 at 8:33
Debora
41
asked Nov 7 at 8:33
Debora
41
asked Nov 7 at 8:33
Debora
41
41
2
In future, I would recommend following the PEP8 Style Guide as it is much more readable. Specifically, take a look at Naming conventions and whitespace in expressions and statements.
– Modelmat
Nov 7 at 8:44
Can you explain the meaning of the value you are apparently trying to converge, perhaps with a reference to the algorithm?
– tripleee
Nov 7 at 10:19
This is to try to figure out the minimum lowest payment I need to pay every month to pay off my credit card debt.I have to use bisection search.
– Debora
Nov 8 at 5:49
add a comment |
2
In future, I would recommend following the PEP8 Style Guide as it is much more readable. Specifically, take a look at Naming conventions and whitespace in expressions and statements.
– Modelmat
Nov 7 at 8:44
Can you explain the meaning of the value you are apparently trying to converge, perhaps with a reference to the algorithm?
– tripleee
Nov 7 at 10:19
This is to try to figure out the minimum lowest payment I need to pay every month to pay off my credit card debt.I have to use bisection search.
– Debora
Nov 8 at 5:49
2
2
In future, I would recommend following the PEP8 Style Guide as it is much more readable. Specifically, take a look at Naming conventions and whitespace in expressions and statements.
– Modelmat
Nov 7 at 8:44
In future, I would recommend following the PEP8 Style Guide as it is much more readable. Specifically, take a look at Naming conventions and whitespace in expressions and statements.
– Modelmat
Nov 7 at 8:44
Can you explain the meaning of the value you are apparently trying to converge, perhaps with a reference to the algorithm?
– tripleee
Nov 7 at 10:19
Can you explain the meaning of the value you are apparently trying to converge, perhaps with a reference to the algorithm?
– tripleee
Nov 7 at 10:19
This is to try to figure out the minimum lowest payment I need to pay every month to pay off my credit card debt.I have to use bisection search.
– Debora
Nov 8 at 5:49
This is to try to figure out the minimum lowest payment I need to pay every month to pay off my credit card debt.I have to use bisection search.
– Debora
Nov 8 at 5:49
add a comment |
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In future, I would recommend following the PEP8 Style Guide as it is much more readable. Specifically, take a look at Naming conventions and whitespace in expressions and statements.
– Modelmat
Nov 7 at 8:44
Can you explain the meaning of the value you are apparently trying to converge, perhaps with a reference to the algorithm?
– tripleee
Nov 7 at 10:19
This is to try to figure out the minimum lowest payment I need to pay every month to pay off my credit card debt.I have to use bisection search.
– Debora
Nov 8 at 5:49