Extending an inversion

Extending an inversion#

Two cases are dealt with here:

  • an inversion that stopped unduly e.g. because the computing time was up or a disk was full or another such issue

  • an inversion that stopped duly but must be extended e.g. the total number of simulations is reached or a better convergence can be asked for.

  1. In case the inversion has been unduly stopped, remove the last directory generated by the CTM (for example, for CHIMERE with periods of 24 hours, the last day available).

  2. Modify the yaml to use the computations which are valid:

    • in obsoper, option autorestart must be True

    • in simulator, option reload_from_previous must be True. If simulator is not specified in the yaml (because it is not necessary when the default cost is used, as is generally the case), specify it as shown in the following example.

mode:
  minimizer:
    df1: 0.5
    epsg: 0.1
    maxiter: 10
    nsim: 25
    plugin:
      name: M1QN3
      version: std
    simulator:
      plugin:
        name: gausscost
        version: std
      reload_from_previous: true
  plugin:
    name: 4dvar
    version: std
  save_out_netcdf: true
obsoperator:
  plugin:
    name: standard
    version: std
    type: obsoperator
  autorestart: True

  1. If the inversion is to be extended, the characteristics of the minimizer linked to the stopping criteria must be changed. For example, for m1qn3, epsg can be decreased and maxiter, nsim can be increased.

  2. the job can then be launched again.