Re: [Orekit Users] CPython interface question

["Petrus Hyvönen" <petrus.hyvonen@gmail.com>]

Hi Piyush,

Can you test which row in your script that triggers the failure? (Either copy /paste or use a editor that can run a selection such as spyder)

Regards
/Petrus



On 24 dec 2012, at 09:32, <piyush@gps.caltech.edu> wrote:

> Hi everyone,
>     I stumbled across orekit when looking for software for orbit propagation.
> I'm trying to propagate given state vectors (position + velocity) for SAR
> satellites in the forward and backward directions by a few minutes. I'm a heavy
> Python user and chose to try the CPython interface. The interface works pretty
> well and allows me to transform data easily between inertial and itrf frames.
> However, everytime I try to propagate the orbit (tried a couple of methods) -
> the program crashes with the following message. I'm not really familiar with
> JCC and have trouble interpreting this error.
> 
> # A fatal error has been detected by the Java Runtime Environment:
> #
> #  SIGSEGV (0xb) at pc=0x00007f44841f7c5a, pid=16722, tid=139932295845632
> #
> # JRE version: 6.0_24-b24
> # Java VM: OpenJDK 64-Bit Server VM (20.0-b12 mixed mode linux-amd64 compressed
> oops)
> # Derivative: IcedTea6 1.11.5
> # Distribution: Ubuntu 12.04 LTS, package 6b24-1.11.5-0ubuntu1~12.04.1
> # Problematic frame:
> # C  [_orekit.so+0x358c5a]  _parseArgs(_object**, unsigned int, char*,
> ...)+0x218a
> #
> 
> 
> Here is my code segment. Any suggestions would be helpful.
> 
> Thanks
> Piyush
> 
> 	setup_orekit_curdir()	   #Reads data and includes initVM
> 
> 	#####Setup the ECEF frame
> 	ecefframe = orekit.FramesFactory.getITRF2005()
> 	ae = orekit.Constants.WGS84_EARTH_EQUATORIAL_RADIUS
> 	flt = orekit.Constants.WGS84_EARTH_FLATTENING
> 	mu = orekit.Constants.WGS84_EARTH_MU
> 	earth = orekit.OneAxisEllipsoid(ae, flt, ecefframe)
> 
> 	######Setup the ECI Frame
> 	eciframe = orekit.FramesFactory.getEME2000()
> 
> 	######Setup time frame
> 	utc = orekit.TimeScalesFactory.getUTC()
> 
> 	#####Read in data from ROI_PAC state vector file	
> 	hdrdata = np.loadtxt('hdr_pts.rsc')
> 
> 	ihr, imin, isec = secs_2_hhmmss(hdrdata[0,0])
> 	ipos = orekit.Vector3D(float(hdrdata[0,1]), float(hdrdata[0,2]),
> float(hdrdata[0,3]))
> 	ivel = orekit.Vector3D(float(hdrdata[0,4]), float(hdrdata[0,5]),
> float(hdrdata[0,6]))
> 	iVect = orekit.PVCoordinates(ipos, ivel)
> 	itime = hdrdata[0,0]
> 	iDate = orekit.AbsoluteDate(2012, 4, 30, ihr, imin, isec, utc)
> 
> 
> 	#######Create transforms using this
> 	eci2ecef = eciframe.getTransformTo(ecefframe, iDate)
> 	ecef2eci = eci2ecef.getInverse()
> 
> 	eVect = ecef2eci.transformPVCoordinates(iVect)
> 	initOrbit = orekit.KeplerianOrbit(eVect, eciframe,iDate, mu)
> 	orb_prop = orekit.KeplerianPropagator(initOrbit)
> 	orb_prop.setSlaveMode()
> 	
> 	startDate = orekit.AbsoluteDate(iDate,float(hdrdata[1,0]-hdrdata[0,0]),
> utc)
> 	finState = orb_prop.propagate(startDate)