`gz` is a required parameter for gravity inversion and `tmi` is required for mag inversion, which prevents inversion of component- or gradient-only data

[nwilliams-kobold]

We’re trying to run a Falcon guv+gxy inversion in geoapps 0.9.2 , and it seems that it is not possible without defining gz?
OptionalValidationError: Cannot set a None value to non-optional parameter: gz_channel.

We are creating the geoh5 and json files directly using geoapps.inversion.potential_fields.gravity.params rather than using the GUI:

json_out = params.GravityParams(
…
    gz_channel_bool = False,
    gz_channel = None,
    guv_channel_bool = True,
    guv_channel = data_uid,
    guv_uncertainty = error_uid,
…
)
json_out.write_input_file(…)

The solution seems to be allowing gz to be optional, but requiring at least 1 of the possible components.

[github-actions]

JIRA issue [GEOPY-952] was created.

[nwilliams-kobold]

It looks like this might be related to this change: d85d6a6#diff-b2146808eb22eb72329ba3b92cab9e47d7875ab323aa506740ff9529a5000562L238 (Line 238 of gravity.constants)

If that is the problem then the same change was also made to the mag inversion code to require TMI (and therefore prevent use of other components without TMI) in line 254 of magnetic_vector.constants from the same PR.

[RichardScottOZ]

Does it matter which one?

[nwilliams-kobold]

We have confirmed that this also occurs in the inversion application too, when selecting only non-gz components:

[nwilliams-kobold]

Does it matter which one?

No. If gz is not supplied it fails.

[nwilliams-kobold]

Can also confirm the same behaviour for mag inversions: If tmi is not supplied, the json file cannot be written.
OptionalValidationError: Cannot set a None value to non-optional parameter: tmi_channel.
(Here I supplied bz instead).

[nwilliams-kobold]

Furthermore I have identified that the issue comes from the default validations that are set. Calling

from geoapps.inversion.potential_fields.gravity import params as grav_params
...
params = grav_params.GravityParams(
    geoh5 = ws.h5file,
    data_object = points.uid, 
    topography_object = surface.uid, 
    guv_channel = data_uid,
    guv_uncertainty = error_uid,
    ...
)

and then calling params.input_file.ui_json['gz_channel'] gives:

{'association': ['Cell', 'Vertex'],
 'dataType': 'Float',
 'group': 'Data',
 'main': True,
 'label': 'Gz (mGal)',
 'parent': 'data_object',
 'optional': True,              << CORRECT
 'enabled': True,               << INCORRECT, but even when I reset this key to False, the error still occurs
 'value': None}

but calling params.validations['gz_channel'] gives:

{'types': [str, uuid.UUID, geoh5py.shared.entity.Entity],
 'association': 'data_object',
 'uuid': None,
 'optional': False,              << INCORRECT
 'one_of': 'data channel'}

Hence the error: OptionalValidationError: Cannot set a None value to non-optional parameter: gz_channel.

[nwilliams-kobold]

Any updates on this ticket? It prevents us from upgrading from 0.8.

[domfournier]

Sorry for the late reply. Should have been fixed on release/0.11.0. We will test on next sprint.