How to compute ln in Org-Mode spreadsheet

Question

Is there a formula to compute the natural logarithm of a number in Org-Mode spreadsheet? For example, to compute ln(1), Excel or Calc formula is =ln(1), what would it be in Org-Mode?

The result should be 0 as ln(1)=0.

Answer 1

You can either use the calc syntax or the elisp syntax.

| x | calc syntax | elisp syntax |
|---+-------------+--------------|
| 1 |           0 |       0.0000 |
| 2 |      0.6931 |       0.6931 |
#+TBLFM: $2=log($1);n4::$3='(log $1);N%.4f

Notice that the output format of the calc syntax depends on the ~/.emacs.d/calc.el parameters.

(plist-put org-calc-default-modes 'calc-language 'latex)
(plist-put org-calc-default-modes  'calc-symbolic-mode t)

| x | calc syntax | elisp syntax |   |
|---+-------------+--------------+---|
| 1 | 0           |       0.0000 |   |
| 2 | \ln{2}      |       0.6931 |   |
#+TBLFM: $2=log($1);n4::$3='(log $1);N%.4f

Answer 2

Well, actually =ln(1) works in org-table, I just tested it. I didn't know because I didn't find it in the documentation...