Re: 971002: netcdf 3 and GMT

>To: address@hidden
>From: Paul Wessel <address@hidden>
>Subject: netcdf 3 and GMT
>Organization: University of Hawaii
>Keywords: 199710022207.QAA22322 netCDF 3

Hi Paul,

> We've converting GMT to use netcdf 3.  All seems well except for one thing:
> 
> Using version 2 code we wrote 
> 
> ncattget (c->cdfid, NC_GLOBAL, "title", (void *)c->title);
> 
> which correctly got the title string.
> Using version 3 this now looks like
> 
> nc_get_att_text (c->cdfid, NC_GLOBAL, "title", c->title);
> 
> But when we run the program that line gives an error:
> Attempt to convert between text & numbers
> 
> and no title is passed back.
> 
> Any ideas?  This is on an Ultra-2 with Solaris 2.5.1 and Sun compilers

Yes, the netCDF-3 interface tries to prevent reading data as text that
was written as numbers, so unless the external type of the "title"
attribute is NC_CHAR, you will get this error message.  If you wrote the
"title" attributes using the NC_BYTE type instead of the NC_CHAR type,
you can get around this by reading the data using nc_get_att_schar()
instead of nc_get_att_text() to read the data into an array of signed
char, for example:

  nc_get_att_schar (c->cdfid, NC_GLOBAL, "title", (signed char*) c->title);

--Russ

_____________________________________________________________________

Russ Rew                                         UCAR Unidata Program
address@hidden                     http://www.unidata.ucar.edu