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bugs - FindDivisions behavior changed?



Bug introduced in 8.0.4 or sooner and fixed in 10.4.1




I seem to recall using FindDivisions as a quick way to get all numbers in an interval that are divisible by a member of some set of integers, e.g.


FindDivisions[{1,100,{2,3,5}}]

gave me lists of all in the range divisible by 2, then 3, then 5, at least if I remember correctly.


Just doing this, I got



FindDivisions::argtu: FindDivisions called with 1 argument; 2 or 3 arguments are expected. >>




A quick look at the docs shows indeed this is the correct format for this operation.


Trying to force the issue with


FindDivisions[{1, 100, {2, 3, 5}}, All, 10]

resulted in



FindDivisions::fdargs: The arguments in Developer`FindDivisions[{1,100,{2,3,5}}, All, 10] are not supported.>>



There are of course simple ways to do the same, I'm just curious when this changed (and why it's still documented), or is it a bug and it should work.



Answer




I submitted this issue to the attention of Wolfram tech support. I received their answer this morning. I quote the relevant part.



I was able to reproduce the issue, and consequently I filed a report with our development team raising the issue.



On the basis of this reply I am tagging the question with .


Although it is not entirely clear from the brief reply I received, I infer that WRI is treating this as an implementation bug and not as a documentation bug.


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