GAMMA Questions

Dear all,

when running S1_coreg_TOPS or S1_coreg_TOPS_dual_pol (doesn't matter) I get for some of my data a singular matrix 2 error when the first iteration for the offset refinement using the spectral diversity in the azimuth overlap region starts:

...
...
...

S1_poly_overlap SLC_20170719_vv_tab 5 1 20170719_vv.az_ovr.poly 1
S1_poly_overlap: Script to determine polygons for overlap regions in Sentinel-1 TOPS data v1.3 28-Nov-2016 uw

generate polygons for azimuth overlaps
SLC_20170719_vv_tab nrows: 1   ncols: 3
RSLC1_IW1: /misc/ra11/neel/crop_lodging/2017_demmin_s1_p146/05_cslc/slc_20170719/20170719_vv_iw2.slc /misc/ra11/neel/crop_lodging/2017_demmin_s1_p146/05_cslc/slc_20170719/20170719_vv_iw2.slc.par /misc/ra11/neel/crop_lodging/2017_demmin_s1_p146/05_cslc/slc_20170719/20170719_vv_iw2.slc.tops_par
azimuth_line_time: 2.0555563e-03
range_pixel_spacing: 2.329562
start_time: 60755.6840410
IW1_valid_lines 26 to 1487  IW1_valid_samples: 263 to 5133
IW1_rows_offset: 1342.000217
determine burst overlap regions within each sub-swath
i,j: 1,1  mli_cols: 263 to 5133   mli_rows: 1368 to 1487
azimuth overlap polygon file: 20170719_vv.az_ovr.poly
*** Land Application Tools: Program poly_math ***
*** Copyright 2018, Gamma Remote Sensing, v1.3 16-Apr-2018 clw/uw ***
*** Mathematical operations on polygonal regions (float data) ***
using command line values for offset and scale for all polygons
copying only data within polygons to output file
offset applied to data within all polygons:        0.00000e+00
scale factor applied to data within all polygons:  1.00000e+00
data lines in the input file: 2854
number of input data blocks: 1

data block: 1   first line offset: 0   last line offset: 2853
polygon: 1   offset:  0.00000e+00   scale:  1.00000e+00
number of points in the bounding box: 584520
polygon:    1  points: 579530

user time (s):         0.020
system time (s):       0.090
elapsed time (s):      0.120

*** DISP Program raspwr ***
*** Copyright 2018, Gamma Remote Sensing, v3.3 12-Oct-2018 clw/cm ***
*** Generate 8-bit greyscale raster image of intensity data ***
OPENMP: number of physically available processors: 24
OPENMP: max. number of threads (program defined): 4
OPENMP: max. number of available threads, (environment variable OMP_NUM_THREADS): 16
OPENMP: number of threads that will be used: 16
FLOAT data: 20170719_vv.rmli.az_ovr
input image width: 5345   height: 2854
range looks: 1   azimuth looks: 1
output image width: 5345   height: 2854
relative scale factor:    1.000  exponent:    0.350
file: 20170719_vv.rmli.az_ovr  ave. intensity:  9.86787e-02  average:  4.02484e-01  scale factor:  2.98149e+02
line 0
line 2000

output image: 20170719_vv.rmli.az_ovr.bmp
lines: 2854  width: 5345

user time (s):         6.620
system time (s):       0.110
elapsed time (s):      0.470

*** Land Application Tools: Program mask_class.c ***
*** Copyright 2015, Gamma Remote Sensing, v4.7 8-Dec-2015 uw/clw ***
*** Set image data values belonging to a single class or set of classes or the complement to a user-defined value ***

input class file: 20170719_vv.rmli.az_ovr.bmp  width:  5345   height:  2854
NOTE: make certain that the input and output files have the same width as the class map file
MODE: Setting pixels belonging to the selected class or classes to null_value

class 1   value: 0

input data filename:  20170713_vv.mli.lt
output data filename: 20170713_vv.mli.lt.az_ovr
input/output data format: floating point complex (32-bit real, 32-bit complex)
complex (32-bit real,imaginary) null value:  0.00000e+00   0.00000e+00

line:      0
line:   1000
line:   2000
total output lines: 2854

user time (s):         0.110
system time (s):       0.060
elapsed time (s):      0.170

offset refinement using spectral diversity in azimuth overlap region iteration 1
SLC_interp_lt_ScanSAR SLC_20170713_vv_tab 20170713_vv.slc.par SLC_20170719_vv_tab 20170719_vv.rslc.par 20170713_vv.mli.lt.az_ovr 20170719_vv.rmli.par 20170713_vv.mli.par 20170719_vv_20170713_vv.off.start RSLC_20170713_vv_tab 20170713_vv.rslc 20170713_vv.rslc.par

ERROR: gaussj: singular matrix 2

Does anybody have an idea in which direction I need to investigate to solve that matter?
Thank you very much,
Julia