[netcdfgroup] NcType problems on Ubuntu 16.04

• To: <netcdfgroup@xxxxxxxxxxxxxxxx>
• Subject: [netcdfgroup] NcType problems on Ubuntu 16.04
• From: <Daniel.Potter@xxxxxxxx>
• Date: Fri, 2 Dec 2016 05:10:31 +0000

Dear netCDF group,


I have encountered some problems with netCDF c++ data types since upgrading to 
Ubuntu 16.04.  In short, the first 6 data types defined in ncType.h work fine 
(e.g. nc_BYTE, nc_CHAR, nc_SHORT, nc_INT, nc_FLOAT and nc_DOUBLE), but the rest 
(including types that I need for my software, nc_STRING, nc_UINT) throw 
NcBadType errors when nc_inq_type is called (from NcType::getName() for 
example).


Previously I was using netCDF 4.1.3 and netCDF c++ 4.2.1 on Ubuntu 14.04 and 
Win7, and everything worked fine.  The netCDF version available by the Ubuntu 
16.04 package manager is 4.4.0, and the netCDF c++ version remains 4.2.1.


The problem is summarised in the attached example, which I compile via:


g++ --std=c++11 types_test.cpp -lnetcdf_c++4 -lnetcdf


The output I get on Ubuntu 16.04 with netCDF 4.40 is:


$

encountered bad type when making a string variable
encountered bad type when making a uint variable
myType = byte
myType = char
myType = short
myType = int
myType = float
myType = double
Type with enum value: 7 throws NcBadType
Type with enum value: 8 throws NcBadType
Type with enum value: 9 throws NcBadType
Type with enum value: 10 throws NcBadType
Type with enum value: 11 throws NcBadType
Type with enum value: 12 throws NcBadType
Type with enum value: 13 throws NcBadType
Type with enum value: 14 throws NcBadType
Type with enum value: 15 throws NcBadType
Type with enum value: 16 throws NcBadType
myType = nc_BYTE
myType = nc_CHAR
myType = nc_SHORT
myType = nc_INT
myType = nc_FLOAT
myType = nc_DOUBLE
myType = nc_UBYTE
myType = nc_USHORT
myType = nc_UINT
myType = nc_INT64
myType = nc_UINT64
myType = nc_STRING
Type with enum value: 13 throws NcBadId
Type with enum value: 14 throws NcBadId
Type with enum value: 15 throws NcBadId
Type with enum value: 16 throws NcBadId

$


The output I get on Ubuntu 14.04 with netCDF 4.1.3 is:


$

myType = byte
myType = char
myType = short
myType = int
myType = float
myType = double
myType = ubyte
myType = ushort
myType = uint
myType = int64
myType = uint64
myType = string
Type with enum value: 13 throws NcBadType
Type with enum value: 14 throws NcBadType
Type with enum value: 15 throws NcBadType
Type with enum value: 16 throws NcBadType
myType = nc_BYTE
myType = nc_CHAR
myType = nc_SHORT
myType = nc_INT
myType = nc_FLOAT
myType = nc_DOUBLE
myType = nc_UBYTE
myType = nc_USHORT
myType = nc_UINT
myType = nc_INT64
myType = nc_UINT64
myType = nc_STRING
Type with enum value: 13 throws NcBadId
Type with enum value: 14 throws NcBadId
Type with enum value: 15 throws NcBadId
Type with enum value: 16 throws NcBadId

$


Is the problem something to do with not have a valid ncid, as the comments from 
ncType.cpp allude too?


// Returns the type name.
string  NcType::getName() const{
  char charName[NC_MAX_NAME+1];
  size_t *sizep=NULL;

  /* We cannot call nc_inq_type without a valid
     netcdf file ID (ncid), which is not *groupid*.
     Working around this for now. */

  ncCheck(nc_inq_type(g_ncid,myId,charName,sizep),__FILE__,__LINE__);
  return string(charName);

};


Any help would be greatly appreciated!


Best regards,

Daniel

#include <iostream>
#include <string>
#include <vector>

#include <netcdf>

int main(void)
{
        netCDF::NcFile ncFile("test.nc", netCDF::NcFile::replace);
        
        try
        {
                std::vector<float> myFloats = { 1., 2., 3., 4., 5. };
                auto ncDim = ncFile.addDim("myFloatsDim", myFloats.size());
                auto ncVar = ncFile.addVar("myFloats", netCDF::ncFloat, 
{ncDim});
                ncVar.putVar(myFloats.data());
        }
        catch (netCDF::exceptions::NcBadType)
        {
                std::cout << "encountered bad type when making a float 
variable" << std::endl;
        }
        
        try
        {
                std::vector<std::string> myStrings = { "a", "bb", "ccc", "dddd" 
};
                auto ncDim = ncFile.addDim("myStringsDim", myStrings.size());
                auto ncVar = ncFile.addVar("myStrings", netCDF::ncString, 
{ncDim});
                std::vector<const char *> myChars;
                for ( auto s : myStrings )
                        myChars.push_back( s.c_str() );
                ncVar.putVar(myChars.data());
        }
        catch (netCDF::exceptions::NcBadType)
        {
                std::cout << "encountered bad type when making a string 
variable" << std::endl;
        }
        
        try
        {
                std::vector<unsigned int> myUints = { 1, 2, 3, 4, 5 };
                auto ncDim = ncFile.addDim("myUintsDim", myUints.size());
                auto ncVar = ncFile.addVar("myUints", netCDF::ncUint, {ncDim});
                ncVar.putVar(myUints.data());
        }
        catch (netCDF::exceptions::NcBadType)
        {
                std::cout << "encountered bad type when making a uint variable" 
<< std::endl;
        }
        
        for (size_t i=1; i<17; ++i)
        {
                try
                {
                        netCDF::NcType * myType = new netCDF::NcType(i);
                        std::cout << "myType = " << myType->getName() << 
std::endl;
                }
                catch (netCDF::exceptions::NcBadType)
                {
                        std::cout << "Type with enum value: " << i << " throws 
NcBadType" << std::endl;
                }
        }

        for (size_t i=1; i<17; ++i)
        {
                try
                {
                        netCDF::NcType myType(i);
                        std::cout << "myType = " << myType.getTypeClassName() 
<< std::endl;
                }
                catch (netCDF::exceptions::NcBadId)
                {
                        std::cout << "Type with enum value: " << i << " throws 
NcBadId" << std::endl;
                }
        }
        
        return 0;
}

• Follow-Ups:
  • Re: [netcdfgroup] NcType problems on Ubuntu 16.04
    • From: Elizabeth A. Fischer