Scheme

Grid

1^st order (1,2) scheme

2^nd order (1,2,3) scheme

3^rd order

(1,2,3,4) scheme

4^th order (1,2,3,4,5) scheme

Grid 1

−1.9867357

(0.666%)

−1.991132154

(0.443%)

−1.9920387

(0.398%)

−1.992431358

(0.378%)

Grid 2

−1.993381972

(0.331%)

−1.995622482

(0.218%)

−1.996072644

(0.196%)

−1.996257356

(0.187%)

Grid 3

−1.995569677

(0.221%)

−1.997066733

(0.146%)

−1.997366868

(0.131%)

−1.997498503

(0.125%)

Grid 4

−1.973488941

(1.325%)

−1.982419735

(0.879%)

−1.984135078

(0.793%)

−1.98505092

(0.747%)

Grid 5

(uniform)

−1.843726

(7.813%)

−1.909891241

(4.509%)

−1.9246767643

3.766%

−1.931826679

(3.408%)