> xeasy
> Contour plot         [cp]
>  
> level and bas 1 -4132.708984
> level and bas 2 -2952.077881
> level and bas 3 -2108.770020
> level and bas 4 -1506.407104
> level and bas 5 -1076.147949
> level and bas 6 -768.819946
> level and bas 7 -549.299988
> level and bas 8 -392.500000
> level and bas 9 -280.500000
> level and bas 10 -200.500000
> level and bas 11 200.500000
> level and bas 12 280.500000
> level and bas 13 392.500000
> level and bas 14 549.299988
> level and bas 15 768.819946
> level and bas 16 1076.147949
> level and bas 17 1506.407104
> level and bas 18 2108.770020
> level and bas 19 2952.077881
> level and bas 20 4132.708984
>  
> Contour plot         [cp]
>  
> level and bas 1 -2066.604492
> level and bas 2 -1476.288940
> level and bas 3 -1054.635010
> level and bas 4 -753.453552
> level and bas 5 -538.323975
> level and bas 6 -384.659973
> level and bas 7 -274.899994
> level and bas 8 -196.500000
> level and bas 9 -140.500000
> level and bas 10 -100.500000
> level and bas 11 100.500000
> level and bas 12 140.500000
> level and bas 13 196.500000
> level and bas 14 274.899994
> level and bas 15 384.659973
> level and bas 16 538.323975
> level and bas 17 753.453552
> level and bas 18 1054.635010
> level and bas 19 1476.288940
> level and bas 20 2066.604492
>