[Bug-gama] questions about Gnu-Gama

[jacques.beilin]

Dear Mr Cepek,

I teach geodesy at ENSG, the IGN (french mapping agency) engineer school.

I try to use Gnu-Gama to process topometric observation made by my 
students. We work at the moment on a dam. We have already processed our 
data with an IGN-made least-square software. I wrote a conversion 
program to tanslate the data from our format to gnu-gama format.

We noticed some strange behaviours with gnu-gama. May be we do not use 
it correctly.

I made some tests with Gnu Gama 1.12 under linux and 1.11 under windows.

I made 2 test with 3 points fixed or 3 point constrained at 1mm.

Under Linux the program creates the output file until the "outlying 
observations" block but it never stops.
Under windows the program stops with  the message "Computation of 
bearing for identical points" with the constrained solution. With fixed 
points it stops without any message.  In both cases we get huge 
outliers. The same input files have been used under windows and linux.

I have also a question about network orientation. Under linux I get the 
message "Inconsistent coordinates and angles: changing internally sign 
of all Y coordinates". What should I put in the header for a frame with 
x-direction pointing to the east and y-direction pointing to the north ?

You will find enclosed our data :
- STATIONS_constrained.xml : input file with 3 points constrained
- STATIONS_fixed.xml : input file with 3 points fixed
- laye_constrained.txt : output file for STATIONS_constrained.xml with 
Gnu-Gama 1.12 under linux
- laye_fixed.txt : output file for STATIONS_fixed.xml with Gnu-Gama 1.12 
under linux
- laye_constrained_winxp.txt : output file for STATIONS_constrained.xml 
with Gnu-Gama 1.11 under windows
- laye_fixed_winxp.txt : output file for STATIONS_fixed.xml with 
Gnu-Gama 1.11 under windows

Best regards,

Jacques Beilin

laye_constrained.txt
Description: Text document

laye_constrained_winxp.txt
Description: Text document

STATIONS_constrained.xml
Description: Text Data

STATIONS_fixed.xml
Description: Text Data

laye_fixed.txt
Description: Text document

laye_fixed_winxp.txt
Description: Text document