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kaikow
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Joined: October 22nd, 2002, 3:04 pm

Accuracy: Calc vs. Excel

June 6th, 2007, 1:45 pm

It seems that there were accuracy issues in version 1.1 of Calc.Any info on whether things have improved in more recent versions of Calc?How does Calc compare with Excel in numerical accuracy?
 
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DominicConnor
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Accuracy: Calc vs. Excel

June 7th, 2007, 7:35 am

Excel has three sets of calculation mode.Sheets are done in extended precision, ie 80 bit.VBA works in a mix of single and double precision (32 and 64 bit)Add-ins are usually 64 bit, but as C++ apps may choose to use extended precision.
 
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kaikow
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Accuracy: Calc vs. Excel

June 7th, 2007, 9:46 am

QuoteOriginally posted by: DCFCExcel has three sets of calculation mode.Sheets are done in extended precision, ie 80 bit.VBA works in a mix of single and double precision (32 and 64 bit)Add-ins are usually 64 bit, but as C++ apps may choose to use extended precision.THe issue is the algorithms used, not the precision.Precision means nothing with faulty algorithms.
 
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MMP
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Joined: August 18th, 2005, 1:18 am

Accuracy: Calc vs. Excel

June 8th, 2007, 3:50 am

QuoteOriginally posted by: kaikowIt seems that there were accuracy issues in version 1.1 of Calc.Any info on whether things have improved in more recent versions of Calc?How does Calc compare with Excel in numerical accuracy?I don't remember what versions I was using when I looked at some of the stats functions in Calc, Excel and Gnumeric, but IIRC Gnumeric was the best, followed by Excel. The differences were not that great (I have no need for high precision stas, so my perception may be far different for someone who needs super high accuracy). Gnumeric had other flaws, but certainly is the fastest for correcting and improving function accuracy.If you need the high accuracy and want to stay in the spreadsheet world, download the code from Ian Smith. http://members.aol.com/iandjmsmith/examples.xlsHis site seems to be down, but the link to the Excel file still works. A newsgroup poster far more skilled than I in this realm has commented numerous times saying how good it is, and that Ian's stuff is better than some dedicated stats packages. EDIT: His site is still up...here is the link to the numerical analysis page. http://members.aol.com/iandjmsmith/iansNApage.htm
Last edited by MMP on June 7th, 2007, 10:00 pm, edited 1 time in total.
 
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kaikow
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Accuracy: Calc vs. Excel

June 8th, 2007, 8:18 am

QuoteOriginally posted by: MMPQuoteOriginally posted by: kaikowIt seems that there were accuracy issues in version 1.1 of Calc.Any info on whether things have improved in more recent versions of Calc?How does Calc compare with Excel in numerical accuracy?I don't remember what versions I was using when I looked at some of the stats functions in Calc, Excel and Gnumeric, but IIRC Gnumeric was the best, followed by Excel. The differences were not that great (I have no need for high precision stas, so my perception may be far different for someone who needs super high accuracy). Gnumeric had other flaws, but certainly is the fastest for correcting and improving function accuracy.If you need the high accuracy and want to stay in the spreadsheet world, download the code from Ian Smith. http://members.aol.com/iandjmsmith/examples.xlsHis site seems to be down, but the link to the Excel file still works. A newsgroup poster far more skilled than I in this realm has commented numerous times saying how good it is, and that Ian's stuff is better than some dedicated stats packages. EDIT: His site is still up...here is the link to the numerical analysis page. http://members.aol.com/iandjmsmith/iansNApage.htmFor those of us who are programmers, it's not difficult to create a DLL with accurate algorithms, but I want to look at this from the perspective of the masses who take on faith that Excel or Calc uses appropriate algorithms. Such users have to stay in the spreadsheet world.When I saw the statements about the accuracy issues in Calc 1.1, I became concerned about the design decisions that went into calc.