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Hi!

I have some org-tables which contain empty fields. I specified :missing "?" to get the right results. When I try to plot them with Gnuplot the empty fields are not exported as '?' but just as empty strings ''. Gnuplot therefore just uses the next non empty field for the value and therefore shifts the columns of the given row.

To make it more concrete:

  #+TBLNAME: data-missing
  | Comment    |    gnutime | milage/km | something else |
  |------------+------------+-----------+----------------|
  | JET        | 2012-01-01 |      1000 |                |
  |            | 2012-02-01 |      2000 |            100 |
  | DUMMY      | 2012-03-01 |      3000 |                |
  |            | 2012-04-01 |      4000 |            100 |
  | OMV        | 2012-05-01 |      5000 |                |
  | OMV PETROM | 2012-06-01 |      6000 |                |
  | OMV PETROM | 2012-07-01 |      7000 |                |
  | OMV        | 2012-08-01 |      8000 |                |
  | BP         | 2012-09-01 |      9000 |                |
  #+begin_src gnuplot :var data=data-missing :exports both :file data-missing.svg :missing "?" :set "xtics nomirror rotate by -45 font \",8\""
  reset
  set xtics nomirror rotate by -45 font ",8"
  set title "Fahr Plot"
  set xdata time
  set timefmt "%Y-%m-%d-%H:%M:%S"
  set xlabel "Time"
  set ylabel "Distance"
  set format y "%.0s T%cm"
  set key top left
  FIT_LIMIT = 1e-36
  m=100
  c=-100000
 
  y(x) = m*x+c
  fit y(x) data using 2:3 via c, m
 
  plot data u 2:3 w lp lw 1 title 'Distance', \
       y(x) title "line fit"
  #+end_src

This is what I get:


When I fill out the empty fields in the first column of the table I get the right result:

I am using Org-mode version 8.3.4. With Org Version 8.2.5h everything works fine.

Thanks,
Harald

Emacs  : GNU Emacs 24.5.1 (i686-pc-mingw32)
 of 2015-04-11 on LEG570
Package: Org-mode version 8.3.4 (8.3.4-47-gaf853d-elpaplus @ c:/Users/harald/AppData/Roaming/.emacs.d/elpa/org-plus-contrib-20160502/)