3d178674-761f-480c-9796-0cff93e227d7 15 6 9 decimal

&[DATE] &[TIME] - &[FILENAME]

x y z f x y * x 3^z * - x y * sin z * 21 mat :

t0 0 : t1 3 : N 200 : 31 line

IC 5021 mat :

f x y z JacobiStiff x y z f 1 el (x diff x y z f 1 el (y diff x y z f 1 el (z diff x y z f 2 el (x diff x y z f 2 el (y diff x y z f 2 el (z diff 23 mat :

Expand symbolic f x y z JacobiStiff y - 3 x 2^* z * + (- x x 3^- y x y * cos * z * x x y * cos * z * x y * sin 23 mat

Substitute by local definitions t Y J x t : y Y 1 el : z Y 2 el : f x y z JacobiStiff 41 line :

t Y J 3 t 2^* Y 2 el * Y 1 el - (- t t 3^- Y 1 el t Y 1 el * cos * Y 2 el * t t Y 1 el * cos * Y 2 el * t Y 1 el * sin 23 mat

Jacobi # # # # # mk52lfa # # # # # mk52lfn 21 line

t Y J 3 t 2^* Y 2 el * Y 1 el - (- t t 3^- Y 1 el t Y 1 el * cos * Y 2 el * t t Y 1 el * cos * Y 2 el * t Y 1 el * sin 23 mat :

J IC t0 t1 200 t Y J mk52lfn :

Rkadapt works fine

J 1 col J 2 col augment

...numerical or analytical computation of the Jacobi matrix.

...numerical Jacobi matrix, which is computed by the routine.

mk52lfa("1:vector", "2:number", "3:number", "4:number", "5:function") - A specialized routine for solving stiff ODE systems using the implicit method based on L-stable (5,2)-method with numerical or analytical computation of the Jacobi matrix. The user must provide a routine for this computation.

mk52lfn("1:vector", "2:number", "3:number", "4:number", "5:function") - A specialized routine for solving stiff ODE systems using the implicit method based on L-stable (5,2)-method with the numerical Jacobi matrix, which is computed by the routine.

x 5 : y 0 : z 0 : 31 sys

x 5 : y 0 : z 0 : 31 mat

x 5 ≡ y 0 ≡ z 0 ≡ 31 sys

50031 mat

My interpretation is that 'mk521fa' would take the f(x,y,z) as is and it would dress the Jacobi

x y z Jacob x 5 ≡ y 0 ≡ z 0 ≡ 31 sys t0 t1 200 x y z f mk52lfa :

Jacob 50031 mat t0 t1 200 x y z f mk52lfa :

Jacob #