## minimallinux 3 years ago Why is error ? 'int object not callable' high = (balance(1 + monthlyInterestRate)**12)/12 http://codepad.org/L6SUqoTC Unfortunately, I have limited idea how this one works it hasn't sunk in yet, maybe I need a breakl

1. MicroBot

u forgot an operator there so maybe thats why?

2. MicroBot

Spend time to fully understand the math in this problem and the bisection method. And stop programming so late at night xD! makes u make mistakes:P Plus, i dont know if im wrong but, wouldn't it be better to assure this will be a float division by dividing it with 12.0 and not 12 ,that could give you an integer division and create wrong results?

3. minimallinux

Yes Ill do that in morning, Thanks (Haven't really got a grip of the bisection method yet)

4. Gianko15

It's very tricky the bisection method, try with a simple example, and gradually make it bigger. Also @MicroBot the monthlyInterestRate (= annualInterestRate/12); is float because the annual rate is always a float number (0.2 or 0.4 or 0.18).

5. TuringTest

while (pay - balance)>= epsilon: This line is wrong. pay is the *monthly* payment according to your code, and since the way you have coded this balance will never change, pay>>balance always so this loop will never terminate. You need to find a way to keep track of the balance (that should be updated every lop btw) that will result from a particular monthly payment. I will tell you that I had to introduce a new variable about the balance to solve this problem, though I'm sure there are more ways.

6. TuringTest

also your pay=(high+low)/2 at the end seems to be on the wrong indent

7. TuringTest

I have no idea what int it thinks you are trying to call, but perhaps it is what @MicroBot says about the high = (balance(1 + monthlyInterestRate)**12)/12 perhaps it thinks you are trying to call a function balance on (1 + monthlyInterestRate)**12 ?? that's just a guess though

8. TuringTest

so yeah, definitely put that operator in there

9. Gianko15

Yeah he miss the * Another tip, epsilon is a tiny value (0.001 for example), as @TuringTest said is an endless loop, try to compare to a difference of values, maybe you can try to compare both balances, the current and the one you get with the pay obtained from your algorithm.

10. MicroBot

@turingtest 1: Yes, about the int problem i was thinking exsactly that...that since there is no operator, it thinks of it as a function call or smthing. 2: About the float division: i was talking again about the same statement high = (balance(1 + monthlyInterestRate)**12)/12 that i believe it should be better written as: high = (balance(1 + monthlyInterestRate)**12)/12.0 but seeing it now...since there is monthlyInterestRate in there it will be a float anyway:P (see @minimallinux when you answer questions late at night and you are tired ,you say things non accurate:P)

11. msmithhnova

The error is due to this high = (balance(1 + ... as microbot said in the first post missing operator. It needs to be high = (balance*(1 + ... notice the addition of the * operator. We understand that * is implied when we look at it but the computer does not, sometimes hard to spot as it 'looks normal' to us.