39964380f1
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@357 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
43 lines
961 B
Prolog
43 lines
961 B
Prolog
%% demo2.pl -- Stasinos Konstantopoulos
|
|
%% konstant@let.rug.nl, Tue Feb 12 2002
|
|
%%
|
|
|
|
%%
|
|
%% This the calculation that needs to be performed, in this case
|
|
%% the sum of [From..To]
|
|
%%
|
|
|
|
calc( From, From, Acc, Res ) :- !,
|
|
Res is Acc + From.
|
|
calc( From, To, Acc, Res ) :- !,
|
|
Acc1 is Acc + To,
|
|
To1 is To - 1,
|
|
calc( From, To1, Acc1, Res ).
|
|
|
|
|
|
%%
|
|
%% We'll pretend the preprocessing was more complicated, and have the
|
|
%% root broadcast how many numbers each processor should do.
|
|
%% Each processor must then figure out which ones to do and call calc/4.
|
|
%%
|
|
|
|
do(0, Num) :-
|
|
!,
|
|
mpi_bcast( Num, 0 ),
|
|
format( 'Proc 0: broadcast ~q.~n', [Num] ).
|
|
do(Rank, _) :-
|
|
!,
|
|
mpi_bcast( Num, 0 ),
|
|
format( 'Proc ~q: had ~q broadcast from 0.~n', [Rank, Num] ).
|
|
|
|
|
|
%%
|
|
%% This is the entry point
|
|
%%
|
|
|
|
start(Num) :-
|
|
mpi_open( Rank, NumProc, ProcName ),
|
|
format( 'Rank: ~q NumProc: ~q, ProcName: ~q~n', [Rank,NumProc,ProcName] ),
|
|
do( Rank, Num ),
|
|
format( 'Rank ~q finished!~n', [Rank] ).
|