Cumulative Column in Org Table

Question

I would like to create a table with Coronavirus case counts for the state of Utah in the United States. I have a table with two columns: a date column and a column of total new cases for that day in my state. I would like Org to generate a third column that is a cumulative sum of all the previous case counts.

The output should look like this:

  |------------------+----+-----|
  | <2020-02-27 Thu> |  0 |   0 |
  | <2020-02-28 Fri> |  1 |   1 |
  | <2020-02-29 Sat> |  0 |   1 |
  | <2020-03-01 Sun> |  0 |   1 |
  | <2020-03-02 Mon> |  0 |   1 |
  | <2020-03-03 Tue> |  0 |   1 |
  | <2020-03-04 Wed> |  1 |   2 |
  | <2020-03-05 Thu> |  1 |   3 |
  | <2020-03-06 Fri> |  2 |   5 |
  | <2020-03-07 Sat> |  2 |   7 |
  | <2020-03-08 Sun> |  1 |   8 |
  | <2020-03-09 Mon> |  0 |   8 |
  | <2020-03-10 Tue> |  1 |   9 |
  | <2020-03-11 Wed> |  3 |  12 |
  | <2020-03-12 Thu> |  5 |  17 |
  | <2020-03-13 Fri> |  6 |  23 |
  | <2020-03-14 Sat> | 13 |  36 |
  | <2020-03-15 Sun> | 11 |  47 |
  | <2020-03-16 Mon> |  8 |  55 |
  | <2020-03-17 Tue> | 22 |  77 |
  | <2020-03-18 Wed> | 13 |  90 |
  | <2020-03-19 Thu> | 31 | 121 |
  | <2020-03-20 Fri> | 27 | 148 |
  | <2020-03-21 Sat> | 33 | 181 |
  | <2020-03-22 Sun> | 69 | 250 |
  |                  |    |     |
  |------------------+----+-----|
  #+TBLFM: $3=$2+@-1$3

But when I run C-u C-c * to recompute the entire table line by line, that generates the error:

row descriptor -1 leads outside table

Also, I would appreciate if anyone knows how to plot this data using gnuplot or perhaps just an ascii plot.

Answer 1

You can use vsum for the cumulative sum as shown in the following Org code.

There are two options for plotting the data with gnuplot. You can either use a meta comment line #+PLOT: or a gnuplot source block. Both cases are shown in the following example.

You have to type [[file:coronaMeta.png]] yourself in the case of the meta line. The source block adds itself a #+RESULTS: and a line with the file link.

#+NAME: corona
#+PLOT: file:"coronaMeta.png" title:"Corona Cases" ind:1 deps:(3)
| Date             | Cases | Cumulative |
|------------------+-------+-------------|
| <2020-02-27 Thu> |     0 |           0 |
| <2020-02-28 Fri> |     1 |           1 |
| <2020-02-29 Sat> |     0 |           1 |
| <2020-03-01 Sun> |     0 |           1 |
| <2020-03-02 Mon> |     0 |           1 |
| <2020-03-03 Tue> |     0 |           1 |
| <2020-03-04 Wed> |     1 |           2 |
| <2020-03-05 Thu> |     1 |           3 |
| <2020-03-06 Fri> |     2 |           5 |
| <2020-03-07 Sat> |     2 |           7 |
| <2020-03-08 Sun> |     1 |           8 |
| <2020-03-09 Mon> |     0 |           8 |
| <2020-03-10 Tue> |     1 |           9 |
| <2020-03-11 Wed> |     3 |          12 |
| <2020-03-12 Thu> |     5 |          17 |
| <2020-03-13 Fri> |     6 |          23 |
| <2020-03-14 Sat> |    13 |          36 |
| <2020-03-15 Sun> |    11 |          47 |
| <2020-03-16 Mon> |     8 |          55 |
| <2020-03-17 Tue> |    22 |          77 |
| <2020-03-18 Wed> |    13 |          90 |
| <2020-03-19 Thu> |    31 |         121 |
| <2020-03-20 Fri> |    27 |         148 |
| <2020-03-21 Sat> |    33 |         181 |
| <2020-03-22 Sun> |    69 |         250 |
|------------------+-------+-------------|
  #+TBLFM: $3=vsum(@I$2..@+0$2)

[[file:coronaMeta.png]]

#+BEGIN_SRC gnuplot :var data=corona :file coronaSrcBlock.png :results graphics
set style data linespoints
set title "Corona Cases"
plot data using 1:3
#+END_SRC

Answer 2

• Initialize the first cell with @1$3=$2. This override the column formula which is correct.
• use orgtbl-ascii-draw for an ascii plot

    |------------------+----+-----+--------------|
    | <2020-02-27 Thu> |  0 |   0 |              |
    | <2020-02-28 Fri> |  1 |   1 |              |
    | <2020-02-29 Sat> |  0 |   1 |              |
    | <2020-03-01 Sun> |  0 |   1 |              |
    | <2020-03-02 Mon> |  0 |   1 |              |
    | <2020-03-03 Tue> |  0 |   1 |              |
    | <2020-03-04 Wed> |  1 |   2 | .            |
    | <2020-03-05 Thu> |  1 |   3 | .            |
    | <2020-03-06 Fri> |  2 |   5 | :            |
    | <2020-03-07 Sat> |  2 |   7 | ;            |
    | <2020-03-08 Sun> |  1 |   8 | c            |
    | <2020-03-09 Mon> |  0 |   8 | c            |
    | <2020-03-10 Tue> |  1 |   9 | c            |
    | <2020-03-11 Wed> |  3 |  12 | l            |
    | <2020-03-12 Thu> |  5 |  17 | V            |
    | <2020-03-13 Fri> |  6 |  23 | W.           |
    | <2020-03-14 Sat> | 13 |  36 | Wh           |
    | <2020-03-15 Sun> | 11 |  47 | WW;          |
    | <2020-03-16 Mon> |  8 |  55 | WWl          |
    | <2020-03-17 Tue> | 22 |  77 | WWWh         |
    | <2020-03-18 Wed> | 13 |  90 | WWWW;        |
    | <2020-03-19 Thu> | 31 | 121 | WWWWWV       |
    | <2020-03-20 Fri> | 27 | 148 | WWWWWWW.     |
    | <2020-03-21 Sat> | 33 | 181 | WWWWWWWWh    |
    | <2020-03-22 Sun> | 69 | 250 | WWWWWWWWWWWW |
    |------------------+----+-----+--------------|
    #+TBLFM: $3=$2+@-1$3::@1$3=$2::$4='(orgtbl-ascii-draw $3 0 250 12)