[Orgmode] Tables: Calculating cumulative and final grades

[Kene Meniru]

Thanks to everyone who helped me with the letter grading and ranking formula for columns 17/Q and 18/R above. I wish to trouble you all again 
with two requests. After incorporating the two solutions above and entering my summer class grades, it was so sweet that I would like two other 
things automated.

  |   |    | Total grades for   |   100 |  100 |   89 |  84 | 100 | 100 | 204 | 
400 | 100 | 100 |         |         |         |   |    |    |
  | ^ |    | each evaluation    |    DG |   EG |   FG |  GG |  HG |  IG |  JG | 
 KG |  LG |  MG |  Single | Overall | Overall |   |    |    |
  |   |    | Percentage weights |     6 |   10 |   10 |  10 |   7 |   7 |  14 | 
 12 |   0 |  24 |     Now |     Now |   Final |   |    |    |
  | ^ | SQ | Student Names      |   E01 |  E02 |  E03 | E04 | E05 | E06 | E07 | 
E08 | E09 | E10 | E-Grade | C-Grade | F-Grade | L | RK | SQ |
  
|---+----+--------------------+-------+------+------+-----+-----+-----+-----+-----+-----+-----+---------+---------+---------+---+----+----|
  | # |  1 | lastA, first       | 95.23 | 87.7 |   76 |  75 | 100 | 100 | 204 | 
    |     |     |    0.00 |   93.67 |   59.95 | A |  1 |  1 |
  | # |  2 | lastB, first       |   100 | 64.7 |   61 |  63 | 100 |  60 | 204 | 
    |     |     |    0.00 |   81.29 |   52.02 | B |  4 |  2 |
  | # |  3 | lastC, first       | 85.69 | 60.2 |   66 |  68 | 100 |  90 | 130 | 
    |     |     |    0.00 |   76.40 |   48.89 | C |  7 |  3 |
  | # |  4 | lastD, first       | 76.15 | 44.6 |   41 |  54 | 100 | 100 |  85 | 
    |     |     |    0.00 |   62.34 |   39.90 | D | 10 |  4 |
  | # |  5 | lastE, first       | 80.92 | 43.6 |   68 |  63 | 100 |  70 | 173 | 
    |     |     |    0.00 |   75.20 |   48.13 | C |  8 |  5 |
  | # |  6 | lastF, first       | 85.69 | 80.4 | 50.5 |  42 | 100 | 100 | 196 | 
    |     |     |    0.00 |   80.17 |   51.31 | B |  5 |  6 |
  | # |  7 | lastG, first       | 95.23 | 56.6 |   55 |  65 | 100 |  60 | 157 | 
    |     |     |    0.00 |   73.85 |   47.27 | C |  9 |  7 |
  | # |  8 | lastH, first       | 80.92 | 50.7 |   64 |  70 | 100 |  90 | 159 | 
    |     |     |    0.00 |   77.60 |   49.66 | C |  6 |  8 |
  | # |  9 | lastI, first       | 95.23 | 73.2 |   88 |  73 | 100 |  70 | 183 | 
    |     |     |    0.00 |   87.61 |   56.07 | B |  2 |  9 |
  | # | 10 | lastJ, first       | 85.69 | 47.2 |   28 |     | 100 |   0 |     | 
    |     |     |    0.00 |   31.26 |   20.01 | F | 11 | 10 |
  | # | 11 | lastK, first       |   100 |   69 |   56 |  77 | 100 | 100 | 164 | 
    |     |     |    0.00 |   83.77 |   53.61 | B |  3 | 11 |
  
|---+----+--------------------+-------+------+------+-----+-----+-----+-----+-----+-----+-----+---------+---------+---------+---+----+----|
  |   |    |                    |       |      |      |     |     |     |     | 
    |     |     |         |         |         |   |    |    |
#+TBLFM: 
$14=($13/$MG)*100;%.2f::$15=(((($E01/$DG)*$4)+(($E02/$EG)*$5)+(($E03/$FG)*$6)+(($E04/$GG)*$7)+(($E05/$HG)*$8)+(($E06/$IG)*$9)+(($E07/$JG)*$10))/($E01+$E02+$E03+$E04+$E05+$E06+$E07))*100;%.2f::$16=((($E01/$DG)*$4)+(($E02/$EG)*$5)+(($E03/$FG)*$6)+(($E04/$GG)*$7)+(($E05/$HG)*$8)+(($E06/$IG)*$9)+(($E07/$JG)*$10)+(($E08/$KG)*$11)+(($E09/$LG)*$12)+(($E10/$MG)*$13);%.2f::$17=if($15<60,F,if($15<70,D,if($15<80,C,if($15<90,B,A))))::$18=find(rsort(@address@hidden),$15)::$19=$2


First is the cumulative grade column 15/O.
Presently, I add the available grades divided by the available total. When I grade each additional assignment, I add that to the total in this 
column's formula manually which gives me the cumulative. Is there a way to automatically do this or am I expecting too much? I have removed 
grades in column K, L, M so I can show the difference in calculation between column O and P. Assuming there are 10 assessments for the class in 
the semester and 7 have been graded. Column O shows the grade for each student as 100% of the total grade. Column P shows the appropriate 
fraction of the total grade for the assessments as a fraction of the overall knowing that there are 3 more assignments ungraded. Column O gives 
me a better snapshot of each students performance at any point in time.

The second problem is numbering the students in column 2/B.
I want to manage the number for each student so that it does not matter when I add or remove a student in the roster. Right now students are 
registering for the fall classes and I add their names according to their alphabetized last names. I have to re-sequence this column constantly. 
I appreciate all the help that anyone can throw at these problems.

--

Kene Meniru
::::::::::::::::::::::::::::
address@hidden