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Segmenttion fault

Added by deepAI M about 5 years ago

Dear Charles,

I am getting the below message after running this line SLC_diff_intf 20170312.slc 20171225.rslc 20170312.slc.par 20171225.rslc.par 20170312_20171225.off 20170312_20171225.sim_unw 20170312_20171225.diff 10 2 0 0 0.2 1 1
is this error ?

SLC-1 phase gradients (rad/sample) range: -0.063576
range spectrum phase gradiant: 0.0000
Segmentation fault (core dumped)

Thank you

Best regards
Pradeep


Replies (5)

Segmenttion fault - Added by Charles Werner about 5 years ago

Hello,
The error is most likely related to the data or parameter files. From the call,
you are not performing range spectral shift filtering, or azimuth filtering. It
is possible that this error comes about through interpolation of the simulated
unwrapped phase data. Can you check how this looks?
There is the program visdt_pwr.py, use the -c option -c 12.56  -m jet.cm   options.

If you cannot find anything specifically wrong with the simulated data, input
data or parameter files. Then could you please make the data available to us
including the slcs, parameter files, and simulated phase.

If possible, please reduce the size of the input data to to the minimum size
that still shows the error.

You can also look at the simulated phase and slc files to see if there are any
NaNs in them using the gamma program replace_values.
A NaN value in the data or simulated phase can lead to a segmentation fault.

Best regards,
Charles

RE: Segmenttion fault - Added by deepAI M about 5 years ago

Hi Charles,

The segmentation fault error problem is solved with tested it on small size (earlier multi look is 10 2 and now, changed to multi look with 30 4, reduces to 860 380 ).

Thank you again for your valuable advice.

Regards,
deep

RE: Segmenttion fault - Added by deepAI M about 5 years ago

Dear Charles,

May I know how to apply range spectrum shift filtering?

Best regards,
Pradeep

RE: Segmenttion fault - Added by Charles Werner about 5 years ago

Hello,
Range spectral shift filtering is the default mode in SLC_diff_intf. It can be
turned on and off using the sps_flg as
described in the gamma documentation accessed via:

gamma_doc SLC_diff_intf

Charles

RE: Segmenttion fault - Added by deepAI M about 5 years ago

Thank you very much Charles

Best regards,
Pradeep

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