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Fix DSST Jacobians for force model parameters

Evan Ward requested to merge dsst-estimate-parameters-986 into develop

Previously the DSST would throw an exception if attempting to compute the jacobian w.r.t. a force model parameter. Now it seems to work.

Changes include:

  • initializing field short period terms when computing Jacobians.
  • using EquinoctialOrbit, not CartesianOrbit for DSST.
  • only consider the short period terms for parameters in the force model that created the short period terms.

I added tests that check running the DSST with zero, one, or two parameters in mean and osculating mode. Had to slightly increase the tolerance on an existing DSST paramter Jacobian test. But the DSST LAGEOS OD test completed in fewer iteration, leading me to believe it was an improvement to the Jacobian.

The changes caused some of the DSST KF tests to no longer work. Those tests seem to create a MEAN DSST propagator, then replace all of the short period terms with OSCULATING ones, without updating the field terms. I'm not sure if this even makes sense from the theory or should be supported, but apparently it worked before. So I adjusted the KF to also update the field terms when it updates the non-field terms.

I also addes some supporting test and debugging code.

Fixes #986 (closed)

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