Hi,
I read and what i conclude (correct me please if i'm wrong) is that the two
methods are equivalents in the case where the iterator represent only one value
so minus_r will behave as an "nq" since it will remove only one value as "nq"
do it !
Also, what i didn't notice is the difference in the case of "gq", for example :
x0 = {1,2,3,4,5}
If the iterator r represent the value {1,2,3}, so
GECODE_ME_CHECK(x0.minus_r(home, r)); will remove these values from x0.And if i
post :GECODE_ME_CHECK(x0.gq(home, 4)); in this case the value {1,2,3} are also
removed from x0.
So, what is here the difference since the two methods remove the whole values
{1,2,3} ?
Thanks.
From: cschu...@kth.se
To: medis...@hotmail.fr; users@gecode.org
Subject: RE: [gecode-users] Difference between minus_r and nq
Date: Tue, 10 Nov 2015 21:08:44 +0100
Hi, No, not all. For the details please read chapter 25 in MPG, it has the full
story! The difference (in short) is that nq removes a single integer value,
whereas minus_r removes a whole set of values represented by a range iterator.
As said, please check MPG. Christian --Christian Schulte,
www.gecode.org/~schulte Professor of Computer Science, KTH,
cschulte@kth.seExpert Researcher, SICS, cschu...@sics.se From:
users-boun...@gecode.org [mailto:users-boun...@gecode.org] On Behalf Of mehdi m
Sent: Tuesday, November 10, 2015 08:36 PM
To: users@gecode.org
Subject: [gecode-users] Difference between minus_r and nq Hi everyone, In the
propagator implementation are the two following methods to remove values from
domains equivalents ? - method 1 :Int::ViewRanges<Int::IntView>
r(x1);GECODE_ME_CHECK(x0.minus_r(home, r)); - method
2GECODE_ME_CHECK(x0.nq(home, val)); Or there is any difference ? I see that the
first one takes a ViewRange and the second can takes an Int directly but what
about correctness and efficiency of pruning ? Thanks.
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