Re: More fortran to oct help

[Paul Thomas]

Zine Smith wrote:

> The help regarding T96 into Octave was great.  Thank
> you.  I am having some trouble thought getting
> everything to link and I have reached my end.  The ld
> error I'm getting from mkoctfile and the wrapper c++
> code is below.  Thank you for your help
>
> Zine
>
> -----Error------
> $ mkoctfile tsyganenko96.cc T96.f
> tsyganenko96.o(.text+0x107c): In function
> `_Z4Ft96RK17octave_value_listi':
> /home/SmithZB/dev/Tsyganenko/tsyganenko96.cc:48:
> undefined reference to `_t96_'
> collect2: ld returned 1 exit statu
>
>  
Zine,

The version below did it for me,  with fortran subroutine T96ONE -  your 
undefined reference  to _t96_ comes about because you invoke t96 in 
F77_FUNC and F77_XFCN.  You sent the linker scurrying off to find a 
symbol _t96_, which it was unable to find.   Args 1 and 2 should be 
lower case and uppercase versions of the name of the fortran subroutine.

Paul T

#include <octave/oct.h>
#include <octave/f77-fcn.h>

extern "C"
{
int F77_FUNC (t96one, T96ONE)\
(const int& IOPT,\
 const double* PARMOD,\
 const double& PS,\
 const double& X,\
 const double& Y,\
 const double& Z,\
 const double& BX,\
 const double& BY,\
 const double& BZ);
}

DEFUN_DLD (t96, args, ,\
 "- Loadable Function: [Bx, By, Bz] = t96 (PM, Ps, x, y, z)\n\
 \n\
 Inputs: PM\t-\tArray(10) with Solar wind pressure in nanopascals in 
PM(1)\n\
   Dst index in PM(2)\n\
   By of the IMF in PM(3)\n\
   & Bz of the IMFin PM(4)\n\
   Ps\t-\tGeotilt angle in radians\n\
   x,y,z\t-\tGSM position (RE)\n\
   Outputs: Bx,By,Bz\t-\tMagnetic field at x,y,z" )           
{
 octave_value_list retval;
 const int dummy_integer = 0;
 Matrix PM;
 const double x=args(2).double_value(),\
              y=args(3).double_value(),\
              z=args(4).double_value();
 const double Ps=args(1).double_value();
 double Bx, By, Bz;

 PM = args(0).matrix_value();

 F77_XFCN (t96one , T96ONE,\
   (dummy_integer, PM.fortran_vec(), Ps, x, y, z, Bx, By, Bz));
 if (f77_exception_encountered)
 {
   error ("unrecoverable error in t96");
   return retval;
 }
 retval(0) = octave_value(Bx);
 retval(1) = octave_value(By);
 retval(2) = octave_value(Bz);
 return retval;
}





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