Re: bug in histogram plot with binary data?

[Ethan M. <merritt@u.washington.edu>]

On Wednesday 30 January 2008 12:42, Ethan Merritt wrote:
> I help is needed from someone more familiar with the binary data modes.
> Anyone care to take over this bug report?


The following one-liner makes your test case work.

However, I am *not* applying this to CVS because I just don't understand
the code well enough.  The binary read code at this point is not parallel 
to the ascii input code, which simply does ++df_datum as it goes.
Why is this different?  Is it correct?  Will it break other things?
I don't know.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
--- gnuplot/src/datafile.c      2008-01-25 12:59:41.000000000 -0800
+++ gnuplot-cvs/src/datafile.c  2008-01-30 23:01:30.000000000 -0800
@@ -4937,7 +4937,7 @@
                }
            }
        } else { /* Not matrix file, general binray. */
-           df_datum = point_count;
+           df_datum = point_count+1;   /* EAM DEBUG */
            if (i != df_no_bin_cols) {
                if (feof(data_fp)) {
                    if (i != 0)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


> On Wednesday 30 January 2008 12:15, Ralf Juengling wrote:
> > 
> > Here you go. The binary data is in intel pentium endianess
> > (whatever that is).
> 
> Thanks. So far as I can tell from a quick test, the problem is
> not specific to histograms.  Any other plot type also gets incorrect
> x coordinates when using the binary read command on that data file.
> If I dump the contents after reading them in, I get this:
> 
> gnuplot>  set style data linespoints
> gnuplot>  plot "histdata.bin" binary array=1:8 format="%int" using 1
> gnuplot> set table
> gnuplot> replot
> 
> # Curve 0 of 1, 7 points
> # Curve title: ""histdata.bin" binary array=1:8 format="%int" using 1"
> # x y type
>  0  102  i
>  0  42  i
>  1  38  i
>  2  28  i
>  3  26  i
>  4  108  i
>  5  156  i
> 
> Can you confirm this on your setup?
> The thing is, I wrote the histogram code so I could probably fix it
> there if necessary.  But I am largely unfamiliar with the binary input
> code, and don't use it much myself.  So I don't know exactly what the
> issue might be.  Surely if it returns the wrong x coordinate in general,
> someone would have noticed by now?  But maybe not.  Or maybe you have
> hit a special case of some sort, though I don't know what it might be.
> 
> 

-- 
Ethan A Merritt            Courier Deliveries: 1959 NE Pacific
Dept of Biochemistry
Health Sciences Building
University of Washington - Seattle WA 98195-7742