"Singular value encountered" error in reactive transport with ats-master

[zexuanxu]

Hi ATS developers,

I'm just trying to bring this on the Github so everyone can keep track of the issue of chemistry merge in ats-master. I encountered the issue below when I was trying to run either my reactive transport case (3D Copper Creek), or the 13_reactive_transport in ats-demos (trans_chem_tests branch)

ERROR: Singular value encountered in ludcmp() on processor: 1 aamax = 0.0000000000000000 row = 1
Jacobian: 1 1 0.0000000000000000 2 0.0000000000000000
Jacobian: 2 1 0.0000000000000000 2 0.0000000000000000

From Ahmad: it's an issue with the order of initialization. Should State go first or PKs? We have been talking about this. Typically ATS initializes PK variables and then State variables. But in reactive transport runs, the primary variables are initialized through State, so State needs to be initialized first otherwise we see this Singular Jacobian issues because things are not properly initialized. And also a few updates in Alquimia_PK.cc break the code.

Thanks
Zexuan

[ecoon]

fixed in refactor of reactive transport.