Re: [OctDev] difficulty with Octave_map.assign(string,Cell)

[paul <ppr...@wi...>]

Michael Hearne wrote:

>I'm getting a segmentation fault when trying to assign a Cell array to an
>Octave_map object, and I don't quite understand why.  What is the appropriate
>way to insert a cell array into an Octave_map?  Below is some sample code and
>the results I get.
>
>Thanks in advance,
>
>Mike
>
>-------------------------------------------------------------
>#include <oct.h>
>#include <ov-cell.h>
>#include <ov-struct.h>
>#include <string>
>
>using namespace std;
>
>DEFUN_DLD(testoctave, args, nargout,
>          "Play around with stuff."){
>	
>	Octave_map tstruct;
>	octave_cell cellnames;
>	message("1","Before cell assignment");
>	cellnames.assign(octave_value(1),octave_value("fred"));
>	cellnames.assign(octave_value(2),octave_value("wilma"));
>	message("2","Before struct 'couple' assignment");
>	tstruct.assign("couple","Flintstones");
>	message("3","Before struct 'names' assignment");
>	tstruct.assign("names",cellnames);
>	message("4","After struct 'names' assignment");
>	octave_value_list retval;
>	return retval;
>}
>-------------------------------------------------------------
>  
>
Michael,
  I got your program to work doing the following:

#include <oct.h>
#include <ov-cell.h>
#include <ov-struct.h>
#include <string>

using namespace std;

DEFUN_DLD(test2, args, nargout,
          "Play around with stuff."){
   
    Octave_map tstruct;
    Cell cellnames(dim_vector(1,2));
    message("1","Before cell assignment");
  cellnames(0)=string("fred");
  cellnames(1)=string("wilma");
    message("2","Before struct 'couple' assignment");
    tstruct.assign("couple","Flintstones");
    message("3","Before struct 'names' assignment");
    tstruct.assign("names",octave_value(cellnames));
    message("4","After struct 'names' assignment");
    octave_value_list retval;
  retval.append(tstruct);
    return retval;
}

As always with writing .oct programs, I'm not sure what made it work. 
I've never had much luck using octave_cell instead of Cell, and one of 
my gripes is that there are no comments in the headers as to what these 
things are intended for.

Paul Probert