Hi All,

I'm encountering a problem with setting projections in a database and I
don't know enough about the process to figure out what I'm doing wrong.

When I process my data using VBA in an Access database (so presumably I
can't use gx's or any EDB calls) I create an Oasis database containing
X,Y,Longitude,Latitude plus other data fields and then make the following
calls to create a projection:

  hIPJXY = Create_IPJ(hGeo)
  iret = SetGXF_IPJ(hGeo, hIPJXY, "Cape / UTM zone 34S", "", "", "",
"Cape,-138,-105,-289,0,0,0,0")

  hIPJLL = Create_IPJ(hGeo)
  iret = SetGXF_IPJ(hGeo, hIPJLL, "", "Cape", "", "", "")

  hIPJ = CreateIPJ_PJ(hGeo, hIPJXY, hIPJLL)

After each of the calls I check the return value and do an iCheckError_SYS
and they all return 0.

Then I make the following calls to assign the projections to the database
(with wrapping lock/unlock calls around the SetIPJ_DB)

  hX = FindSymb_DB(hGeo, hDB, "X", DB_SYMB_CHAN)
  hY = FindSymb_DB(hGeo, hDB, "Y", DB_SYMB_CHAN)
  .
  iret = SetIPJ_DB(hGeo, hDB, hX, hY, hIPHXY)
  .

and then

  hLON = FindSymb_DB(hGeo, hDB, "Longitude", DB_SYMB_CHAN)
  hLAT = FindSymb_DB(hGeo, hDB, "Latitude", DB_SYMB_CHAN)
  .
  iret = SetIPJ_DB(hGeo, hDB, hLON, hLAT, hIPHLL)
  .

Once again I check return values and errors and all is OK.

My problem is that when I open the database and check the projection on the
X,Y columns, the projection and transform information is correct, but the
Local Transform information is listed as <unknown>. Does this mean the there
is no Local Transform defined, in which case why do the SetGXF_IPJ and
SetIPJ_DB not report a problem? Or does it mean that the database has a
Local Transform defined but it does not know what it's name is? The latter
is preferable to the former, but I think that it's probably the former.

I'd gladly supply the Local Transform name (from the datumtrf.csv or
ldatum.csv files) to the SetGXF_IPJ call, but the only format I could get to
work is the one I've used above.

Any suggestions/solutions to this problem would be greatly appreciated.

Many thanks
John Paine




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