Corrected I/O bug when periodic conditions are activated

[arango]

There are couple of bugs in mp_scatter2d and mp_scatter3d when either EW_PERIODIC or NS_PERIODIC are activated. This only happen when processing input fields from NetCDF files. The periodic applications are usually configured with analytical fuctions instead of NetCDF files. I was using the wrong structure to determine the global number of points to process in the I- and J-directions. The computational structure BOUNDS(ng) was used instead of the I/O structure IOBOUNDS(ng). The correct code is to use:

      SELECT CASE (MyType)
        CASE (p2dvar, p3dvar)
          Io=IOBOUNDS(ng) % ILB_psi
          Ie=IOBOUNDS(ng) % IUB_psi
          Jo=IOBOUNDS(ng) % JLB_psi
          Je=IOBOUNDS(ng) % JUB_psi
          Ioff=0
          Joff=1
        CASE (r2dvar, r3dvar)
          Io=IOBOUNDS(ng) % ILB_rho
          Ie=IOBOUNDS(ng) % IUB_rho
          Jo=IOBOUNDS(ng) % JLB_rho
          Je=IOBOUNDS(ng) % JUB_rho
          Ioff=1
          Joff=0
        CASE (u2dvar, u3dvar)
          Io=IOBOUNDS(ng) % ILB_u
          Ie=IOBOUNDS(ng) % IUB_u
          Jo=IOBOUNDS(ng) % JLB_u
          Je=IOBOUNDS(ng) % JUB_u
          Ioff=0
          Joff=0
        CASE (v2dvar, v3dvar)
          Io=IOBOUNDS(ng) % ILB_v
          Ie=IOBOUNDS(ng) % IUB_v
          Jo=IOBOUNDS(ng) % JLB_v
          Je=IOBOUNDS(ng) % JUB_v
          Ioff=1
          Joff=1
        CASE DEFAULT                              ! RHO-points
          Io=IOBOUNDS(ng) % ILB_rho
          Ie=IOBOUNDS(ng) % IUB_rho
          Jo=IOBOUNDS(ng) % JLB_rho
          Je=IOBOUNDS(ng) % JUB_rho
          Ioff=1
          Joff=0
      END SELECT

I also corrected mp_gather2d and mp_gather3d. Non-periodic applications are fine. The issue here is that in periodic applications the computational I-RHO (EW_PERIODIC) and J-RHO (NS_PERIODIC) starts at 1 instead of 0.

Many thanks to Paul Budgell for ​reporting this problem and giving a good clue.