- From: Andrew Eisenberg <andrew.eisenberg@us.ibm.com>
- Date: Fri, 9 Apr 2004 14:59:21 -0400
- To: public-qt-comments@w3.org
- Message-ID: <OFC8CE6F00.00C6DA31-ON85256E71.00680D47-85256E71.00684F9F@us.ibm.com>
I believe that "le" and "ge" return the wrong values when NaN values are provided for either of the two operands. Consider the following query: let $x := 1.0e0 let $nan := xs:double('NaN') return $x eq $nan, (: will return false :) $x lt $nan, (: will return false :) $x gt $nan, (: will return false :) $x le $nan, (: will return true :) $x ge $nan, (: will return true :) $x ne $nan (: will return true :) I believe that "le" and "ge" should return false to be consistent with IEEE 754. They return true because: 1) The definition of op:numeric-less-than and op:numeric-greater-than in F&O both contain the following: "If $arg1 or $arg2 is NaN, the function returns false." 2) The Binary Operator table in XQuery, B.2 Operator Mapping, contains the following: A ge B numeric numeric fn:not(op:numeric-less-than(A, B)) xs:boolean A le B numeric numeric fn:not(op:numeric-greater-than(A, B)) xs:boolean To effect the change I suggest, change the that two rows of the Binary Operator table to the following: A ge B numeric numeric op:numeric-greater-than(A, B) or op:numeric-equal(A,B) xs:boolean A le B numeric numeric op:numeric-less-than(A, B) or op:numeric-equal(A,B) xs:boolean -- Andrew -------------------- Andrew Eisenberg IBM 4 Technology Park Drive Westford, MA 01886 andrew.eisenberg@us.ibm.com Phone: 978-399-5158 Fax: 978-399-7012
Received on Friday, 9 April 2004 14:59:55 UTC