胶片19:用消息传递方法求解拉普拉斯方程的节点程序

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• DIMENSION PHINEW(NLOC+2), PHIOLD(NLOC+2)
• NLOC=NTOT/NPROC
• I1=2
• NLOC1=NLOC + 1
• IF (PROCNUM.EQ.NPROC-1 .or. PROCNUM.EQ.0) NLOC1=NLOC1-1
• BEGIN 　TEST = 0
• SOURCE = PHIOLD(NLOC1)
• IF(PROCNUM.EQ.NPROC-1) SOURCE = "DUMMY"
• DEST = PHIOLD(1)
• IF(PROCNUM.EQ.1)DEST = "DUMMY"
• CALL MPSHIFT(+1, SOURCE, DEST)
• SOURCE = FOLD(I1)
• IF(PROCNUM.EQ.0) SOURCE = "DUMMY"
• DEST = PHIOLD(NLOC1+1)
• IF(PROCNUM.EQ.NPROC-1) DEST = "DUMMY"
• CALL MPSHIFT(-1, SOURCE, DEST)
• DO 1 I=I1,NLOC1
• TEMP = 0.5 * (PHIOLD(I-1) + PHIOLD(I+1))
• TEST = AMAX1(TEST,ABS(TEMP-PHIOLD(I)))
• 1 　　　　PHINEW (I) = TEMP
• DO 2 I=I1, NLOC1
• 2 　　　　PHIOLD(I) = PHINEW(I)
• CALL GLOBALMAX (TEST)
• IF (TEST>CONVG) GO TO BEGIN
• ELSE STOP

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Copyright: NPACT