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Subject: [OASIS Issue Tracker] Issue Comment Edited: (OFFICE-916) PublicComment: ODFF: yet more suggestions
[ http://tools.oasis-open.org/issues/browse/OFFICE-916?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15110#action_15110 ] Eike Rathke edited comment on OFFICE-916 at 11/27/09 1:10 PM: -------------------------------------------------------------- Several topics in that comment, marking my comments on each with [ed:] PMT - Constraints should have Nper>0 and integer - For clarity, should specify that with PayType=1 the first payment is made on the same day the loan is taken out. - The formula is unstable at very low rates. Better to use an approximation, but Calc at least does not do so, and will produce #VALUE! errors. Excel 97 similarly gives #DIV/0! [ed:] Broken out to OFFICE-2219 CORREL - Currently as defined, also allows different dimensions for the two parameters - if this is intended should be explicitly stated (NB Calc expects the same dims). [ed:] That's OFFICE-2175 - Also it's a redundant function - it's identical to Pearson. [ed:] the current draft states that, no action needed. PV - Payment can be omitted if fv is given. [ed:] Broken out to OFFICE-2220 DISC - should divide by YEARFRAC, not multiply I think. [ed:] present in current draft, no action needed. SYD - "sum-of-years' digits method" This phrase appears to be copied from Excel. - I'd suggest either "sum- of-years' digits method" or "sum of years'-digits method". - Formula is at: http://wiki.services.openoffice.org/w/index.php?title=Documentation/How_Tos/Calc:_SYD_function [ed:] Broken out to OFFICE-2221 DDB - "I don't know how to put this into the equations." - See: http://wiki.services.openoffice.org/wiki/Documentation/How_Tos/Calc:_DDB_function [ed:] Broken out to OFFICE-2222 DOLLARDE - Does not return currency; returns a number. [ed:] Same for DOLLARFR function. Broken out to OFFICE-2223 TBILLEQ - Excel gives the formula: "TBILLEQ is calculated as TBILLEQ = (365 x rate)/360-(rate x DSM), where DSM is the number of days between settlement and maturity computed according to the 360 days per year basis." That's wrong - should be (365 x rate)/[360-(rate x DSM)]. Also: using the 360 day year is vital information which needs to be included. - "bond-equivalent yield for a treasury bill" is probably lifted from Excel's Help, and comes across as jargon; needs more explanation, especially for non-US people. [ed:] Broken out to OFFICE-2224 ISPMT - "amortized investment" is jargon, possibly not readily understood except in the US. It gets no useful hits from Google. [ed:] Broken out to OFFICE-2225 ODDFYIELD - doesn't need to say "yield per 100 units" - yield is irrespective of this. [ed:] Broken out to OFFICE-2226 XNPV - Excel documentation gives the formula. It's based on 365 days only. They've missed out a minus sign. More detail is required to define this function. - Excel's help also seems to have an error - I don't think it is *necessary* to have a negative entry - first entry could be a payment. The day count appears to be the actual day count (366 in a leap year). [ed:] Broken out to OFFICE-2227 FTEST - "Summary: Returns the result of an F test (the probability that two datasets have come from the same total population)" Excel says it tests the probability that the *variances* are not significantly different (which is not the same as coming from the same total population). - "An F-test returns the one-tailed probability" Excel currently describes this as the 2-tailed probability. I believe that is correct (see http://www.coventry.ac.uk/ec/~nhunt/pottel.pdf). Old versions of Excel eg 97 describe it as one tailed. It would be worth someone with real knowledge checking this out. [ed:] Broken out to OFFICE-2228 VDB - http://wiki.services.openoffice.org/wiki/Documentation/How_Tos/Calc:_VDB_function has a rather more detailed explanation, and a link to (different) bugs in Calc and Excel. [ed:] Broken out to OFFICE-2229 was (Author: erack): Several topics in that comment, marking my comments on each with [ed:] PMT - Constraints should have Nper>0 and integer - For clarity, should specify that with PayType=1 the first payment is made on the same day the loan is taken out. - The formula is unstable at very low rates. Better to use an approximation, but Calc at least does not do so, and will produce #VALUE! errors. Excel 97 similarly gives #DIV/0! [ed:] TODO: add constraints and PayType=1 definition, and a note that the formula may be unstable at very low rates. CORREL - Currently as defined, also allows different dimensions for the two parameters - if this is intended should be explicitly stated (NB Calc expects the same dims). [ed:] That's OFFICE-2175 - Also it's a redundant function - it's identical to Pearson. [ed:] the current draft states that, no action needed. PV - Payment can be omitted if fv is given. [ed:] TODO: check how that should work. DISC - should divide by YEARFRAC, not multiply I think. [ed:] present in current draft, no action needed. SYD - "sum-of-years' digits method" This phrase appears to be copied from Excel. - I'd suggest either "sum- of-years' digits method" or "sum of years'-digits method". [ed:] TODO: any native English speaker who can provide insight? - Formula is at: http://wiki.services.openoffice.org/w/index.php?title=Documentation/How_Tos/Calc:_SYD_function [ed:] TODO: add formula. DDB - "I don't know how to put this into the equations." - See: http://wiki.services.openoffice.org/wiki/Documentation/How_Tos/Calc:_DDB_function [ed:] TODO: add formula. DOLLARDE - Does not return currency; returns a number. [ed:] TODO: change return to Number. Same for DOLLARFR function. TBILLEQ - Excel gives the formula: "TBILLEQ is calculated as TBILLEQ = (365 x rate)/360-(rate x DSM), where DSM is the number of days between settlement and maturity computed according to the 360 days per year basis." That's wrong - should be (365 x rate)/[360-(rate x DSM)]. Also: using the 360 day year is vital information which needs to be included. [ed:] TODO: add formula. - "bond-equivalent yield for a treasury bill" is probably lifted from Excel's Help, and comes across as jargon; needs more explanation, especially for non-US people. [ed:] TODO: any native English speaker knowledgeable in that domain? ISPMT - "amortized investment" is jargon, possibly not readily understood except in the US. It gets no useful hits from Google. [ed:] TODO: any native English speaker knowledgeable in that domain? ODDFYIELD - doesn't need to say "yield per 100 units" - yield is irrespective of this. [ed:] TODO: is it? what about the Redemption parameter then, that says "the redemption value per 100 currency units face value". XNPV - Excel documentation gives the formula. It's based on 365 days only. They've missed out a minus sign. More detail is required to define this function. [ed:] TODO: who can provide insight? - Excel's help also seems to have an error - I don't think it is *necessary* to have a negative entry - first entry could be a payment. The day count appears to be the actual day count (366 in a leap year). [ed:] TODO: who can provide insight? FTEST - "Summary: Returns the result of an F test (the probability that two datasets have come from the same total population)" Excel says it tests the probability that the *variances* are not significantly different (which is not the same as coming from the same total population). [ed:] TODO: who can provide insight? - "An F-test returns the one-tailed probability" Excel currently describes this as the 2-tailed probability. I believe that is correct (see http://www.coventry.ac.uk/ec/~nhunt/pottel.pdf). Old versions of Excel eg 97 describe it as one tailed. It would be worth someone with real knowledge checking this out. [ed:] TODO: who can provide insight? VDB - http://wiki.services.openoffice.org/wiki/Documentation/How_Tos/Calc:_VDB_function has a rather more detailed explanation, and a link to (different) bugs in Calc and Excel. [ed:] TODO: check that. > Public Comment: ODFF: yet more suggestions > ------------------------------------------ > > Key: OFFICE-916 > URL: http://tools.oasis-open.org/issues/browse/OFFICE-916 > Project: OASIS Open Document Format for Office Applications (OpenDocument) TC > Issue Type: Bug > Components: OpenFormula > Affects Versions: ODF 1.2 > Reporter: Robert Weir > Assignee: Eike Rathke > Priority: Blocker > Fix For: ODF 1.2 > > > Copied from office-comment list > Original author: "David King" <openoffice@drking.plus.com> > Original date: 31 Jul 2008 20:30:12 -0000 > Original URL: http://lists.oasis-open.org/archives/office-comment/200807/msg00112.html -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://tools.oasis-open.org/issues/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
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