Changed order of multiplication in Times[a, b, c] in version 6?!

*To*: mathgroup at smc.vnet.net*Subject*: [mg77568] Changed order of multiplication in Times[a, b, c] in version 6?!*From*: Andrew Moylan <andrew.j.moylan at gmail.com>*Date*: Wed, 13 Jun 2007 07:27:20 -0400 (EDT)

I think the order in which the pairwise multiplication in Times[a, b, c] has changed between version 5.2 and version 6! Can anyone comment on this? Example: Here are three exact numbers whose product is Sqrt[-1]: Times[(1 + I)*10^2000, (1 + I)*1/2*10^-2000, 1] Here are those numbers in approximate form, labelled a, b, and c: {a, b, c} = { 1.`15.954589770191005*^2000*(1 + I), 5.`15.954589770191005*^-2001*(1 + I), 1. + 0.*I }; Here are their various pairwise products: Inputting: { a*b, b*c, a*c } yields the output: { 0``15.653559774527023 + 1.`15.653559774527023*I, 0. + 0.*I, 1.`15.954589770191005*^2000 + 1.`15.954589770191005*^2000*I } So far, all these results are identical between versions 5.2 and 6. Now consider a*b*c. Here is what is given version 5.2: 0``15.653559774526984 + 1.`15.653559774526984*I This happens to be the right answer, because it has done the multiplication in the order (a*b)*c. Here is what is given for a*b*c in version 6: 0. + 0.*I This happens to be the wrong answer, because it has done the multiplication in the order a*(b*c).