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Estimated hours taken: 0.1 Add the DPPD (dozens of problems in partial deduction) suite to the tests directory.
67 lines
1.6 KiB
Mathematica
67 lines
1.6 KiB
Mathematica
/*
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The "map.reduce" Benchmark
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Part of the DPPD Library.
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General Description
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Specialising the higher-order map/3 (using call and =..) for the
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higher-order reduce/4 in turn applied to add/3. The benchmark program
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uses built-ins but no negations. The benchmark illustrates that
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partial deduction can be used to make declarative higher-order
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programming in Prolog/LP efficient.
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The benchmark program
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*/
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:- module map_reduce.
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:- interface.
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:- pred map_reduce is semidet.
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:- implementation.
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:- import_module list, run, map_impl.
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map_reduce :-
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map_reduce_add([[1,2],[1,2,3]],[_L1,_L2]),
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map_reduce_add([[],[1,2],[5,6,7],[8,9,10]],Res1),
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use(Res1),
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map_reduce_add([[],[1,2],[5,6,7],[],[8,9,10],[11,12],
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[13,14],[15],[16]],Res2),
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use(Res2).
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/*
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The partial deduction query
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:- map(reduce_add,L,R).
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The run-time queries
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:- map(reduce_add,[[1,2],[1,2,3]],[L1,L2]).
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:- map(reduce_add,[[],[1,2],[5,6,7],[8,9,10]],Res).
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:- map(reduce_add,[[],[1,2],[5,6,7],[],[8,9,10],[11,12],
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[13,14],[15],[16]],Res).
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Example solution
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With the ECCE partial deduction system one can obtain the following
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program (which runs more than 12 times faster than the original):
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map__1([],[]).
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map__1([X1|X2],[X3|X4]) :-
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reduce__3(X1,X3),
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map__1(X2,X4).
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reduce__3([],0).
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reduce__3([X1|X2],X3) :-
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reduce__3(X2,X4),
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X3 is '+'(X1,X4).
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_________________________________________________________________
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Michael Leuschel / K.U. Leuven / michael@cs.kuleuven.ac.be
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*/
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