[I am also cross posting to functional to get clarification on rounding rule sepcification mentioned in http://www.mifos.org/knowledge/functional-specs/accounting-in-mifos#currency -and-rounding-rules
> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On > Behalf Of Adam Monsen > Sent: Thursday, January 17, 2008 7:35 AM > To: Mifos Developer Mailing List > Subject: SPAM-LOW: [Mifos-developer] Rounding Rules Questions > > On Sun, 2007-12-16 at 16:08 +0545, Soham Dhakal wrote: > [...] > > I implemented code to divide the Principal into equal installments, > > and calculate interest. > > I'm not familiar with Equal Principle Payments, but here's a > spreadsheet that shows current rounding error for flat > interest calculations: > > http://rapidshare.com/files/84396603/Loan_Discrepancies.ods > SHA-1 checksum: f01feb8716d4c4a9215faab78c52bba66f6893bf > > The "rounding to tenths" column shows the effect of > mid-calculation when figuring out loan interest. Filling out > a spreadsheet like this to check your calculations against > what Mifos generates might be helpful in figuring out what's going on. > > It's in OpenOffice.org format. [soham] Thanks. I will look into this. > > > However there is a function in LoanBO->applyRounding which > is adding > > some amount to the principal. For e.g. I had 15,000 pricipal and 24 > > installments with 2 weeks as frequency and for the first > payment the > > principal should be (15000/24)=625, and the interest should > be 144.23. > > But after going through applyRounding it comes to 625.8 and 144.2 > > I wouldn't assume that applyRounding() is working correctly > for what you want to do. For instance, note that every time > Money.add() or > Money.subtract() is called from applyRounding(), > BigDecimal.setScale() is used to re-scale the actual amount > prior to obtaining a complete result. Perhaps this is a bug > since I would expect high precision to be maintained > throughout the calculation, and rounding to be performed just > before returning a value. [soham] I agree. In any case, it seems applyRounding is trying to implement a business logic but I am doubting whether its being done correctly. As I test this more I will share my findings. > > Also, looks like AccountingRules.DigitsAfterDecimal is used > for the scale. I feel like this might be a bug. I assumed > AccountingRules.DigitsAfterDecimal was only for display purposes. [soham] Yes, it looks like that's how it is implemented currently. > [...] > > "The system should adjust the last installment (increase or > decrease) > > for loan accounts to account for the amount change due to rounding. > > Example, if the actual repayment due = 181.95 and after rounding it > > becomes= 181, system should add the 0.95 to the last > installment due." > > > > Does this mean only the LAST installment should be > adjusted? Because > > it looks like each installment was being adjusted (now this > could be > > because I did not know how to set the rounding > configuration properly).. > [soham]Perhaps PMs can shed some light on this, i.e. how should the above mentioned rule apply for different rounding options. > > > 3. Other than the functional specs, is there documentations > on how to > > configure this or what the values mean? (I understand that > there is a > > new and improved configuration process coming out of 1.1) > > Hopefully Kim answered all the configuration questions [soham] Yes, it seems to have worked for me for now > -- > Adam Monsen > > > -------------------------------------------------------------- > ----------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Mifos-functional mailing list Mifos-functional@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mifos-functional
