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Add missing equs
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Eric Brown
Eric Brown
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equs = Join[equ1, equ2];
cinits = Join[cinitsX, cinitsLambda];
vars = Join[X, Lambda];
DE = Join[equs, cinits] /. solU /. parms;

cinits = Join[cinitsX, cinitsLambda];
vars = Join[X, Lambda];
DE = Join[equs, cinits] /. solU /. parms;

equs = Join[equ1, equ2];
cinits = Join[cinitsX, cinitsLambda];
vars = Join[X, Lambda];
DE = Join[equs, cinits] /. solU /. parms;
Update time endpoints
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Eric Brown
Eric Brown
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solDE = NDSolve[DE, vars, {t, 0, 0.01tf}];
Plot[Evaluate[vars /. solDE], {t, 0, 0.01tf}]

solDE = NDSolve[DE, vars, {t, 0, 0.01}];
Plot[Evaluate[vars /. solDE], {t, 0, 0.01}]

solDE = NDSolve[DE, vars, {t, 0, tf}];
Plot[Evaluate[vars /. solDE], {t, 0, tf}]
Give location of my repo of PSOPT model
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Eric Brown
Eric Brown
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I know that BVPs are tough problems to solve, so I tried an alternative implementationalternative implementation in my personal fork of PSOPT pseudospectral code, as well as the trapezoidal method in Mathematica. These are direct solvers (vs. the Pontryagin indirect method) and also have problems with these equations. I have come to conclusion that there's something fishy or extreme stiffness.

I know that BVPs are tough problems to solve, so I tried an alternative implementation in my personal fork of PSOPT pseudospectral code, as well as the trapezoidal method in Mathematica. These are direct solvers (vs. the Pontryagin indirect method) and also have problems with these equations. I have come to conclusion that there's something fishy or extreme stiffness.

I know that BVPs are tough problems to solve, so I tried an alternative implementation in my personal fork of PSOPT pseudospectral code, as well as the trapezoidal method in Mathematica. These are direct solvers (vs. the Pontryagin indirect method) and also have problems with these equations. I have come to conclusion that there's something fishy or extreme stiffness.

Source Link
Eric Brown
Eric Brown
  • 4.4k
  • 1
  • 19
  • 37