Refactor of the Radau Transcription#1233
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…method.
RadauNew (dymos/transcriptions/pseudospectral/radau_new.py) is a new Radau implementation with the following improvements over the original:
- Tighter solve_segments loop via RadauIterGroup, enabling forward/backward shooting without a phase-level Newton solve over the full trajectory
- Exposes initial_states:{name} and final_states:{name} as explicit phase-level variables (_has_initial_final_states = True), replacing StateInputComp
- Removes the redundant boundary ODE system; initial/final control values and rates are sourced directly from ControlInterpComp (control_boundary_values:*, control_boundary_rates:*)
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robfalck
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Coverage is 79.317% — robfalck:radau_new_bug into OpenMDAO:master. No base build found for |
…er the previous Radau transcription.
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Summary
RadauNew was failing the vanderpol_delay_mpi case due to an odd sizing issue.
We found a duplicate connection both at the transcription level and within the RadauIterGroup.
Removing the transcription-level dupliation removed the sizing issue.
The behavior was such that OpenMDAO was acting as if it expected local sizes for
src_indicesrather than the global size. Still unclear why this error manifested in the way it did.This refactor makes the additional boundary ODE option (defaulting it to OFF for existing behavior). In some cases having this extra ODE might improve numerical conditioning, but this implementation is true
Related Issues
Backwards incompatibilities
None
New Dependencies
None