example for direct evaluation of an input moment tensor

[carltape]

It is often very helpful to be able to specify a fixed set of coordinates for a moment tensor (say: Mw, lune longitude, lune latitude, strike, dip, rake) and then evaluate the misfit with observed waveforms, and also generate the various plots (including waveform fits). Could we please add such an example in the documentation? Basically this would be a degenerate grid search using a grid with no volume. I think that for new users this would reinforce the underlying forward-solving that is happening thousands of times, whether within a grid search or sampling-based approach. Thanks.

[rmodrak]

To plot observed and synthetic waveforms, we could do something like

from mtuq import MomentTensor
from mtuq.graphics import plot_waveforms1

mt = MomentTensor([mrr,mtt,mpp,mrt,mrp,mtp])
plot_waveforms1(filename,data, greens.get_synthetics(mt), stations, origin, header=None)

Agreed, it could be helpful to work this into the documentation.

[rmodrak]

Here is how one could modify any of the examples/ scripts:

    mt_dict = {
        "Mrr": -5800435174432632.0,
        "Mtt": 789342714264084.5,
        "Mpp": 5011092460168549.0,
        "Mrt": 3034156721905327.0,
        "Mrp": 2110077787951300.2,
        "Mtp": 2602039428905879.0,
        }

    mt_array = list(mt_dict.values())
    mt = MomentTensor(mt_array)


    plot_data_greens2(event_id+'DC_waveforms.png',
        data_bw, data_sw, greens_bw, greens_sw, process_bw, process_sw, 
        misfit_bw, misfit_sw, stations, origin, mt, lune_dict)

[rmodrak]

Alternatively, one could generate the synthetics first and pass them directly

    from mtuq.graphics import plot_waveforms2

    synthetics_bw = greens_bw.get_synthetics(mt)
    synthetics_sw = greens_sw.get_synthetics(mt)


    plot_waveforms2(event_id+'DC_waveforms.png',
        data_bw, data_sw, synthetics_bw, synthetics_sw, stations, origin)

[rmodrak]

Attached is a complete script illustrating the above

direct_evaluation.py

[rmodrak]

a "misfit function evaluation" page could be added here?

https://mtuqorg.github.io/mtuq/user_guide/06.html