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Parasitic roots of various cyclic linear multistep methods
1. Tischer's formulas
All cyclic linear multistep methods were designed to only have root at 1, and all other parasitic roots to be zero.
See Tischer, Peter E. and Sacks-Davis, Ron: “A New Class of Cyclic Multistep Formulae for Stiff Systems”.
2. Donelson & Hansen formulas
See Donelson III, John and Hansen, Eldon: “Cyclic Composite Multistep Predictor-Corrector Methods”, SIAM Journal on Numerical Analysis, Vol 8, 1971, pp.137—157.
DH1
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | 0.00000000 | 1.00000000 |
| 1 | 0.00000000 | 0.00000000 | 0.00000000 |
| 2 | 0.00000000 | 0.00000000 | 0.00000000 |
DH2
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | -0.31605416 | 0.94874115 | 1.00000000 |
| 1 | -0.31605416 | -0.94874115 | 1.00000000 |
| 2 | 1.00000000 | 0.00000000 | 1.00000000 |
DH3
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | 0.00000000 | 1.00000000 |
| 1 | 0.04526646 | 0.00000000 | 0.04526646 |
| 2 | 0.00000000 | 0.00000000 | 0.00000000 |
DH4
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | 0.00000000 | 1.00000000 |
| 1 | -0.09090909 | 0.00000000 | 0.09090909 |
| 2 | 0.00000000 | -0.00000000 | 0.00000000 |
DH5
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | 0.00000000 | 1.00000000 |
| 1 | -0.01125522 | 0.93329189 | 0.93335976 |
| 2 | -0.01125522 | -0.93329189 | 0.93335976 |
| 3 | 0.00000000 | 0.00000000 | 0.00000000 |
DH6
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | 0.00000000 | 1.00000000 |
| 1 | -0.37892727 | -0.00000000 | 0.37892727 |
| 2 | 0.13825231 | 0.00000000 | 0.13825231 |
| 3 | 0.00000000 | 0.00000000 | 0.00000000 |
3. Mihelcic's formulas
See Matija Mihelčić (Mihelcic) and K. Wingerath: “A(α)-stable Cyclic Composite Multistep Methods of Orders 6 and 7 for Numerical Integration of Stiff Ordinary Differential Equations”, ZAMM, Band 61, 1981, pp.261—264
Mihelcic4
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | 0.00000000 | 1.00000000 |
| 1 | 0.50107560 | 0.00000000 | 0.50107560 |
| 2 | -0.42506560 | 0.00000000 | 0.42506560 |
Mihelcic5
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | 0.00000000 | 1.00000000 |
| 1 | -0.38334289 | 0.00000000 | 0.38334289 |
| 2 | -0.21218358 | 0.00000000 | 0.21218358 |
Mihelcic6
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | -0.00000000 | 1.00000000 |
| 1 | -0.90745413 | -0.00000000 | 0.90745413 |
| 2 | 0.41922349 | 0.00000000 | 0.41922349 |
| 3 | 0.06530404 | -0.00000000 | 0.06530404 |
Mihelcic7
| root | real | imaginary | absolute value |
|---|---|---|---|
| 0 | 1.00000000 | 0.00000000 | 1.00000000 |
| 1 | 0.16549909 | -0.00000000 | 0.16549909 |
| 2 | 0.09946611 | 0.00000000 | 0.09946611 |
| 3 | 0.02567147 | -0.00000000 | 0.02567147 |
| 4 | -0.00642008 | 0.00000000 | 0.00642008 |