From owner-bug-octave at bevo dot che dot wisc dot edu  Thu Dec 19 13:21:37 1996
Subject: Re: fscanf reads strange values on Octave 2.0 /linux
From: "John W. Eaton" <jwe at bevo dot che dot wisc dot edu>
To: Tapani Stipa <Tapani dot Stipa at fimr dot fi>
cc: bug-octave at bevo dot che dot wisc dot edu
Date: Thu, 19 Dec 1996 13:21:04 -0600

On 19-Dec-1996, Tapani Stipa <stipa at kuohu dot fimr dot fi> wrote:

: I would be very much for the option that Octave should read its native
: precision with the "%f" format, as some sort of intuition would suggest (I
: think Matlab does it this way? cannot test now ... this would of course
: not be an excuse by itself ...). 

I think this makes sense.  I've appended a patch if you'd like to try it.

: Just wondering: is there any need to read single precision floats if there
: is no internal format for them? 

The only reason that I can think of is that you might want to see what
the representation will be if the number is read as a float first.
But that doesn't seem like a very good reason now.

Thanks,

jwe


Thu Dec 19 12:13:42 1996  John W. Eaton  <jwe at bevo dot che dot wisc dot edu>

	* oct-stream.cc (octave_base_stream::do_scanf):
	Don't treat %l{e,f,g} differently from %{e,f,g}.
	(octave_base_stream::do_oscanf): Likewise.


Index: oct-stream.cc
===================================================================
RCS file: /home/jwe/src/master/octave/src/oct-stream.cc,v
retrieving revision 1.11
diff -c -r1.11 oct-stream.cc
*** oct-stream.cc	1996/12/08 04:02:46	1.11
--- oct-stream.cc	1996/12/19 19:16:15
***************
*** 887,895 ****
--- 887,897 ----
  do_scanf_conv (istream&, const char*, int*, Matrix&, double*, int&,
  	       int, int, bool);
  
+ #if 0
  template void
  do_scanf_conv (istream&, const char*, float*, Matrix&, double*, int&,
  	       int, int, bool);
+ #endif
  
  template void
  do_scanf_conv (istream&, const char*, double*, Matrix&, double*, int&,
***************
*** 982,1001 ****
  
  		case 'e': case 'f': case 'g':
  		  {
! 		    if (elt->modifier == 'l')
! 		      {
! 			double tmp;
! 
! 			do_scanf_conv (is, fmt, &tmp, mval, data,
! 				       count, nr, max_size, discard); 
! 		      }
! 		    else
! 		      {
! 			float tmp;
  
! 			do_scanf_conv (is, fmt, &tmp, mval, data,
! 				       count, nr, max_size, discard); 
! 		      }
  		  }
  		  break;
  
--- 984,993 ----
  
  		case 'e': case 'f': case 'g':
  		  {
! 		    double tmp;
  
! 		    do_scanf_conv (is, fmt, &tmp, mval, data, count,
! 				   nr, max_size, discard);
  		  }
  		  break;
  
***************
*** 1231,1238 ****
--- 1223,1232 ----
  template octave_value
  do_oscanf_num_conv (istream&, const char*, int*, bool);
  
+ #if 0
  template octave_value
  do_oscanf_num_conv (istream&, const char*, float*, bool);
+ #endif
  
  template octave_value
  do_oscanf_num_conv (istream&, const char*, double*, bool);
***************
*** 1298,1315 ****
  
  	    case 'e': case 'f': case 'g':
  	      {
! 		if (elt->modifier == 'l')
! 		  {
! 		    double tmp;
  
! 		    retval = do_oscanf_num_conv (is, fmt, &tmp, discard);
! 		  }
! 		else
! 		  {
! 		    float tmp;
! 
! 		    retval = do_oscanf_num_conv (is, fmt, &tmp, discard);
! 		  }
  	      }
  	      break;
  
--- 1292,1300 ----
  
  	    case 'e': case 'f': case 'g':
  	      {
! 		double tmp;
  
! 		retval = do_oscanf_num_conv (is, fmt, &tmp, discard);
  	      }
  	      break;