Financial Formulas

[David REMD]

Can someone point me, if it exists, to a library of financial formulas converted to Lua, please? I am working on a financial program and don't understand how to convert the financial formulas. I have attached a screen shot of a mortgage calculator I am building. I have the formula to calculate the monthly payment and it works perfectly. I am looking for the Lua formulas to solve for...

1. Loan Amount
2. Interest Rate
3. Term
4. Principal & Interest

There will be other financial calculations performed elsewhere within the project. Having a complete library would be very helpful. Thank you in advance for any help that can be provided.

[David REMD]

I forgot to include the payment formula should anyone ever need it.

-- Loan amount
Pv = s2n(Input.GetText("Input2"));

-- Interest rate
Rate = Input.GetText("Input3")/1200;

-- Amortization term months
nPer = s2n(Input.GetText("Input4"));

-- Calculate the P&I payment
PiPMT = Math.Round((((Rate)+(Rate)/(Math.Pow(1+(Rate),nPer)-1))*Pv),2);

Input.SetText("Input5", PiPMT);

[colc]

have a look at - https://sourceforge.net/projects/lib...ematicsforlua/
may help??
I'm not good with finance maths
Cheers

[David REMD]

Thank you, colc! This is exactly what I was in need of. I will get a lot of use from the function!

There is 1 functions that does not seem to be correct (rate) and I can't get the (nper) to go.

function rate(fv, pv, n, type) - Missing a variable (pmt).

http://help.eclipse.org/mars/topic/o....8.html#189421

function nper(i, pmt, pv, fv, type) - Returns 0. I am confident I am passing the correct variables.

http://help.eclipse.org/mars/topic/o....8.html#189131

[David REMD]

My mistake. I guess I was getting bug eyed at 2 AM. The (nper) function works! The only loose end is the (rate) function. I need a bit of help with that one. Thanks gain!

[David REMD]

Formula to solve for Present Value (Loan Amount). This works! I hope it helps someone.

-- Interest rate
nInt = s2n(Input.GetText("Input3")/1200);

-- Amortization term months
nPer = s2n(Input.GetText("Input4"));

-- Monthly payment
nPmt = s2n(Input.GetText("Input5"));


Pv = nPmt/( nInt+(nInt/(Math.Pow(1+nInt,nPer)-1)))

Input.SetText("Input2", Pv);

[telco]

can i ask what font you are using on your project? Thanks

[David REMD]

The font is Tahoma.