skip the write of CHAR_DATA when it is empty

[prasad-sawantdesai]

user = getenv('USER');
%tmp1=shot
%tmp2=run

backend="hdf5";
shot=1050
run=1
machine='test'
if backend=='mdsplus'
    idx = imas_create_env ('ids',shot,run,0,0,user, convertStringsToChars(machine),'3')   % for MDS+ backend
elseif backend=='hdf5'
    idx = imas_create_env_backend (shot,run,user,convertStringsToChars(machine),'3',13); % for HDF5 backend
else
    display('no valid backend given, return')
end

hom_time_value=1
clear core_profiles
cp = ids_init('core_profiles')
cp.ids_properties.comment = 'test';
cp.ids_properties.homogeneous_time = hom_time_value;

cp.time=1.0

%working
%nt=1;

%not working
nt=7736;

%cp.profiles_1d=ids_allocate('core_profiles','profiles_1d',nt);
cp.profiles_1d=ids_allocate('core_profiles','profiles_1d',nt);

% Fill cp.time 
cp.time = linspace(0.1, 773.6, nt);

tmp31=cp

ids_put(idx,'core_profiles',cp);

disp ('Closing database')
imas_close(idx);