series,x,y
"Field error, residual norm=1",1,0.10132118364233778
"Field error, residual norm=1",2,0.025330295910584444
"Field error, residual norm=1",3,0.011257909293593086
"Field error, residual norm=1",4,0.006332573977646111
"Field error, residual norm=1",6,0.0028144773233982714
"Field error, residual norm=1",8,0.0015831434944115277
"Field error, residual norm=1",12,0.0007036193308495678
"Gradient error, residual norm=1",1,0.3183098861837907
"Gradient error, residual norm=1",2,0.15915494309189535
"Gradient error, residual norm=1",3,0.1061032953945969
"Gradient error, residual norm=1",4,0.07957747154594767
"Gradient error, residual norm=1",6,0.05305164769729845
"Gradient error, residual norm=1",8,0.039788735772973836
"Gradient error, residual norm=1",12,0.026525823848649224