org-mode table element selection WITH blanks elements

[Niclas Borlin <niclas.borlin@cs.umu.se>]

Hi,

How do you send a list of elements from a table, including blank cells, 
to an elisp function?

I have the table below with points on exam questions in columns 2-4. The 
second row contains the maximum number of points for each question. The 
student rows contain the actual points received. I want to compute the 
maximum possible sum for a student, to be updated while I grade the 
questions.

I have written an elisp function that takes two lists as arguments and 
does the necessary computations. However, the standard selection 
argument ignores blank elements. In the function call below, the 
function will receive the (fontified) lists '("3" "4") '("6" "4" "6") 
and '("6" "2") '("6" "4" "6"), respectively. I need a selection where 
each blank element is kept as, e.g., fontified "". Thus, I would like 
the function to receive '("3" "4" "") '("6" "4" "6"), etc.

Is that possible?

Have tried google and the org manual to no avail.

#+NAME: PTS
|           | Q1| Q2| Q3|     | Max |
|-----------+---+---+---+-----+-----|
|           | 6 | 4 | 6 | Sum | Sum |
|-----------+---+---+---+-----+-----|
| Student 1 | 3 | 4 |   |   7 |  13 |
| Student 2 | 6 |   | 2 |   8 |  12 |
#+TBLFM: @3$6..@>$6='(sum-with-defaults '(@0$2..@0$4) '(@2$2..@2$4)))

Thanks,
/Niclas Börlin
--
Niclas Borlin, PhD                  email: Niclas.Borlin@cs.umu.se
Department of Computing Science     phone: +46 (0)90-786 68 32
Umea University                       fax: +46 (0)90-580 14
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