velocityStd and change of reference as post-processing

[David Bekaert]

Dear Mintpy developers,

I have a mintpy time-series processed and am now making sub-set velocity maps, while also changing the reference location:

     timeseries2velocity.py  timeseries_ramp_demErr.h5 -o velocity_2018_summer.h5  -s 20180416 -e 20181014

     spatial_filter.py velocity_2018_summer.h5
     view.py velocity_2018_summer_lowpass_gaussian.h5 velocity -u cm -v -20 20 --ref-lalo 36.75 -119.75 --coastline --figtitle "2018 Summer"  --nodisplay -o velocity_2018_summer.png
     view.py velocity_2018_summer_lowpass_gaussian.h5 velocityStd -u cm -v -20 20 --ref-lalo 36.75 -119.75 --coastline --figtitle "2018 Summer"  --nodisplay -o velocityStd_2018_summer.png

From the results, i understand that view.py offsets based on the value of the reference location such it gets referenced to 0.

Although for the velocity that works as expected, it leads to negative velocity standard deviation.

I would like to demonstrate the uncertainty to grow away from the reference point.

I am wondering what is the best location for me to set the reference during the post processing.

I understand there is no option in timeseries2velocity for reference point.

Thank you for any pointers,

Best,

David

[Yunjun Zhang]

Hi David,

The --ref-lalo option in view.py is simply offsetting on the fly during the plotting, and won’t re-calculate the velocity STD with respect to the new reference point, as you have pointed out. 

You could run “reference_point.py timeseries_ramp_demErr.h5 --lat 36.75 --lon -119.75 --write-data” to re-referencing your time-series file, then generate the new velocity file with timeseries2velocity.py. 

I am wondering what is the best location for me to set the reference during the post processing.

I would recommend after the phase correction, to the final displacement time-series, same as what you have done.

Best,

Yunjun

--
You received this message because you are subscribed to the Google Groups "MintPy" group.
To unsubscribe from this group and stop receiving emails from it, send an email to mintpy+un...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/mintpy/20a025e7-e5a1-44ee-b72f-735f1b82a969%40googlegroups.com.