High-Order Compact Difference Scheme and Multigrid Method for Solving the 2D Elliptic Problems

Table 2

Maximum absolute error and convergence rate of the CDS and the FOC scheme with Re=100 for Problem 2.

	CDS				FOC
	Num	CPU	Error	Rate	Num	CPU	Error	Rate
1/8	8	0.000	5.59(-1)		6	0.000	1.35(-1)
1/16	10	0.000	1.07(-1)	2.39	8	0.016	8.77(-3)	3.94
1/32	10	0.031	2.43(-2)	2.14	8	0.047	5.52(-4)	3.99
1/64	9	0.125	6.05(-3)	2.01	9	0.172	3.46(-5)	4.00
1/128	10	0.328	1.51(-3)	2.00	9	0.390	2.16(-6)	4.00
1/256	9	1.078	3.78(-4)	2.00	9	1.391	1.35(-7)	4.00