[R] Error: value of 'SET_CXTAIL' must be a char or NULL, not a 'char'

[Søren Højsgaard]

so it looks as though the error message is a little buggy (it should
print TYPEOF(v), not TYPEOF(x), or maybe it should test x, not v.)   But
I don't really know what it's doing.  Are you using a STRSXP somewhere
that is expecting a CHARSXP?

Duncan Murdoch

No; the code that produces the error is given below; but it does not occur on every occasion...
I am puzzled...
 
Regards
Søren
 
 

SEXP rconipm(SEXP S, SEXP K, SEXP Glist, SEXP mode)
{
  R_len_t  nG=length(Glist);
  SEXP ans, Sdims, Kdims,  Gitem, Giidims;
  int  nrS, ncS, nrK, ncK, nrgen, ncgen, ii, jj, Gii, idx;
  double *modep, *rS, *rK, *rG, *ansp, rans;
  Sdims = getAttrib(S, R_DimSymbol);
  nrS = INTEGER(Sdims)[0];  ncS = INTEGER(Sdims)[1];
  rS  = REAL(S);
  Kdims = getAttrib(K, R_DimSymbol);
  nrK = INTEGER(Kdims)[0];  ncK = INTEGER(Kdims)[1];
  rK  = REAL(K);
  PROTECT(ans = allocVector(REALSXP,nrK*ncK));
  ansp = REAL(ans);
  PROTECT(mode = coerceVector(mode, REALSXP)) ;
  modep = REAL(mode);
  idx = 0;
  for (Gii=0; Gii<nG; Gii++){
    Rprintf("Generator %i\n", Gii); 
    Gitem   = VECTOR_ELT(Glist, Gii);
    Giidims = getAttrib(Gitem, R_DimSymbol);    
    nrgen   = INTEGER(Giidims)[0];  
    ncgen   = INTEGER(Giidims)[1];
    
    rG = REAL(Gitem);
    //printmatd(rG, &nrgen, &ncgen);
    //modnewton(rS, rK, &nrS, rG, &nrgen, &ncgen);
  }
  
  UNPROTECT(2);
  return(ans);
}


________________________________

Fra: Duncan Murdoch [mailto:murdoch at stats.uwo.ca]
Sendt: lø 19-04-2008 20:05
Til: Søren Højsgaard
Cc: r-help at stat.math.ethz.ch
Emne: Re: [R] Error: value of 'SET_CXTAIL' must be a char or NULL, not a 'char'



On 19/04/2008 1:18 PM, Søren Højsgaard wrote:
> Dear List
> On windows XP using R.2.6.2 I get the message
> 
> Error: value of 'SET_CXTAIL' must be a char or NULL, not a 'char'
> 
> in connection with calling C code (using the .Call interface). I have been unable to find any info on this (in Writing R extensions). Can anyone help me with understanding this error? (In case it helps in tracking the problem: I pass two matrices and a list of several matrices to my C function).

The code that produces that error message is in memory.c:

#ifdef USE_ATTRIB_FIELD_FOR_CHARSXP_CACHE_CHAINS
SEXP (SET_CXTAIL)(SEXP x, SEXP v) {
#ifdef USE_TYPE_CHECKING
     if(TYPEOF(v) != CHARSXP && TYPEOF(v) != NILSXP)
        error("value of 'SET_CXTAIL' must be a char or NULL, not a '%s'",
              type2char(TYPEOF(x)));
#endif
     /*CHECK_OLD_TO_NEW(x, v); *//* not needed since not properly traced */
     ATTRIB(x) = v;
     return x;
}
#endif /* USE_ATTRIB_FIELD_FOR_CHARSXP_CACHE_CHAINS */

so it looks as though the error message is a little buggy (it should
print TYPEOF(v), not TYPEOF(x), or maybe it should test x, not v.)   But
I don't really know what it's doing.  Are you using a STRSXP somewhere
that is expecting a CHARSXP?

Duncan Murdoch