Grid Size

${\text{Error}}_{\text{relative}}$

RMS

$L_2$

$L_{\infty }$

11 ´ 11

0.0741

0.0173

0.1899

0.0713

21 ´ 21

0.0341

0.0283

0.5934

0.0428

31 ´ 31

0.0123

0.0362

1.1231

0.0232

41 ´ 41

0.0099

0.0428

1.7538

0.0155

51 ´ 51

0.0090

0.0485

2.4713

0.0136