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piecewise - Bug in PiecewiseExpand and Mod with assumptions


Bug introduced in 9.0 or earlier and fixed in 10.4



The following code using PiecewiseExpandand Modgives the wrong answer


PiecewiseExpand[Mod[n, m], m > 0, Integers]


0




tested in Mathematica v 10.2.0 Windows 7 64 and partially discussed on early version of this question.


Wolfram Technical Support case identification : [CASE:3442254]


Can anybody reproduce this problem in other systems?



Answer



As indicated in the header, this bug has been fixed as of Mathematica 10.4.0:


$Version                                                                

(* 10.4.0 for Linux x86 (64-bit) (February 26, 2016) *)


PiecewiseExpand[Mod[n, m], m > 0, Integers]                             

(* Mod[n, m] *)

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