doubleForColumn not working, int does (Swift)

Question

I am pulling some data from a table. NAME is a string, LONGITUDE and LATITUDE are doubles.

The string is retrieved correctly. However if I try and get LONGITUDE as a doubleForColumn (which is what it is) I get a compiler error:

Cannot invoke 'Append' with an argument list of type (Double).

If I use int (which is isn't) the compiler lets it through but returns 0.

Any ideas?

locationNames.append(resultSet.stringForColumn("NAME"))
locationLongitude.append(resultSet.doubleForColumn("LONGITUDE"))
locationLatitude.append(resultSet.intForColumn("LATITUDE"))