Re: [sc-dev] Statistical Functions Implementation

2006-10-23 Thread Niklas Nebel
Leonard Mada wrote: I was wondering what coding algorithm does Calc use when implementing the various statistical functions? REASON === Although different formulas are mathematically identical, they give different *error estimates* when coded on a computer. EXAMPLE The variance

Re: [sc-dev] Statistical Functions Implementation

2006-10-23 Thread Leonard Mada
OK, I have found that most of the code is in sc/source/core/tool/interpr*.cxx, especially in interpr3.cxx and interpr5.cxx. I do know some C++, but unfortunately have very limited time (I also work hard on the statistical wiki page,

Re: [sc-dev] Statistical Functions Implementation

2006-10-23 Thread Leonard Mada
I noticed that Calc calculates the SUM in the same order as that of the data cells. However I was reading somewhere (though do not remember anymore where) that it is best to calculate the sum by: 1. ordering the numbers from smallest to largest (as absolute numbers, i.e. without sign) 2. adding

[sc-dev] Status of ooo-build patches

2006-10-23 Thread Niklas Nebel
Hi, Some people complain that a large number of Calc patches is piling up at ooo-build and we at Sun are ignoring or delaying them. To counter this impression, we (the core Calc team at Sun) went through the Calc section of the list at http://go-oo.org/ooo-build/patches/src680/apply, and

Re: [sc-dev] Statistical Functions Implementation

2006-10-23 Thread Leonard Mada
Hi, I was thinking again on the sum issue. Indeed, if you read my last post (the TestCase with the Spreadsheet where 3 columns with the *same* data yielded different results), there is a problem in the summation of cells. PROBLEM The sum is one of the most elemental operations in a