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Subject: [OASIS Issue Tracker] Commented: (OFFICE-2385) 5.4.7 Infix Operator"="
[ http://tools.oasis-open.org/issues/browse/OFFICE-2385?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17587#action_17587 ] Dennis Hamilton commented on OFFICE-2385: ----------------------------------------- I did a couple of back-of-the-envelope trials with epsilon = tolerance*b^(1-p) assuming b=2 and p=1 and the result doesn't look right. OK, the principle is interesting, but the formula needs work. If, for exponent 0, the absolute value of a nonzero fraction is taken to be in the range 1/b <= f < 1, it would appear that b^(-p) is wanted. We can worry about an exact conversion later, if we decide to provide precision of this sort around comparison approximation tolerances. > 5.4.7 Infix Operator "=" > ------------------------ > > Key: OFFICE-2385 > URL: http://tools.oasis-open.org/issues/browse/OFFICE-2385 > Project: OASIS Open Document Format for Office Applications (OpenDocument) TC > Issue Type: Bug > Components: OpenFormula > Affects Versions: ODF 1.2 Part 2 CD 2 > Reporter: Patrick Durusau > > General commentary under 5.4.7 Infix Operator "=" deleted. > Created JIRA issue to call attention to it. > "Note that in most implementations, numbers are computed using fixed-length representations in base 2 or 16, using a matissa and an exponent. This means that values such as 0.1 cannot be exactly represented (just as 1/3 cannot be exactly represented in base 10 using decimal notation). As a result, (0.1*10) will not have the same bit representation as 1. Since many spreadsheet users do not understand how computers typically represent numbers, applications may attempt to hide these differences by allowing "nearly" equal numbers to be considered equal, but applications are not required to do so. > Note that in some user interfaces this is displayed or accepted as "=="." -- 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