Apache OpenOffice (AOO) Bugzilla – Issue 66735

amend brackets for inputs starting with number with algebraic sign

Last modified: 2013-08-07 15:12:27 UTC

In issue 24271 we found out that there seems to be some worrying concerning correct interpretation of mathematical expressions starting with and only containing an operation with a single number with algebraic sign like '=-2^4' and similar. This would be more clearly if OOo would change that input '=-2^4' to '=(-2)^4'

IMHO not a practicable way and unnecessary as the minus in '=-4^2' can't be anything else as a simple marker for a negative number, so the result is absolutly correct.

IMHO, If auto change (like Gnumeric), the input =-4^2 should be automatically change to =-(4)^2, following math software (R, Scilab, maxima,...) that result -16. But in that case, all combination should be tested : -(4^2) ???...

In Google, Have yous tried to type -4^2 ? It resuts -(4^2) = -16.

Issue 24271 has been closed, but it is still a big BUG. -4^2 = -16 !!! ALWAYS Software, that does NOT conform to this is wrong. You do not have in mathematics an "inverse sign" operator, therefore "-" is really a minus before anything else. * IF you want to raise the number "-4" to sqare, THEN you have to type: (-4)^2 * -4^2 = -(4^2) = -16 * -3! = -(3!) * -x^2 = -(x^2) !!!! ** you never interpret -x^2 = (-x)*(-x) = x^2 !!!! FALSE # the operators '^' AND '!' have highest left-side precedence (BUT NOT right-sided, e.g. -2^3^4 = -2^(3^4)=-(2^(3^4)) ) R v2.4.0: -4^2 = -16 Octave v2.1.73: -4^2 = -16 (I will ask a collegue next week to test Mathematica, too)

I was told the results for *Mathematica* (v5.(x)): It is as expected: -4^2 = -16 !!! Mathematica is a reference program in mathematics, so this should be viewed as written by the almighty. I do not have access to mathematica myself, but I am confident that the person I asked, actually tested this (and did NOT tell me what he thinks is correct). As noted in a previous post, other mathematical software (like Scilab, maxima, octave, R) interpret it the same way. As I mentioned, you do *NOT* have an "inverse sign" operator in mathematics. "-" is only the substraction. IF you want to specify the number "-4" you have to type "(-4)" !!!! BASTA. Why does gnumeric interpet it differently? Interesting question and I believe the answer is as follows: # -4^2 = -16 AND NOT +16, which is wrong # BUT many spreadsheet users were used to get +16 in Excel, # so gnumeric let those users calculate what they expected, # BUT changed the syntax to be correct, so people NOT accustomed to this BUG would know (and see) that it is NOT what they expect So, I can only recommend that Calc adopts this same strategy. This way, professionals can live with this bug, because Calc would tell them: > when people who use this spreadsheet write =-4^2 > they usually mean =(-4)^2; so does Calc.

Similar isues : http://www.openoffice.org/issues/show_bug.cgi?id=24271 http://www.openoffice.org/issues/show_bug.cgi?id=26755 Please close duplicates.

Here is the similar discussion for Gnumeric: http://bugzilla.gnome.org/show_bug.cgi?id=115941 ... with a sensible conclusion. Why wouldn't we do the same job ?

Resolving this issue as duplicate of issue 26755 that now also has more details and pointers. Please transfer your votes. *** This issue has been marked as a duplicate of 26755 ***

Closing dup.