org-spreadsheet: formatting chops off units

[Kyle Andrews <kyle.c.andrews@gmail.com>]

Hello everyone,

I want to use an org-spreadsheet to perform unit conversions for me.

| Mass (g) | Mass (lb)     |
|----------+---------------|
| 300 g    | 0.66138679 lb |
| 23 kg    | 50.706320 lb  |
| 50 Mg    | 110231.13 lb  |
#+TBLFM: $2=uconvert($1, lb)


I made the table above, but can't figure out how to format the output. I
tried using the ;%.2f notation shown in the manual, but it cuts the
units off for some reason.

Here is what org-table displays with ;%.2f appended onto my table
formula:

| Mass (g) | Mass (lb)     |
|----------+---------------|
| 300 g    | 0.66          |
| 23 kg    | 50.71         |
| 50 Mg    | 110231.13     |
#+TBLFM: $2=uconvert($1, lb);%.2f


Here is what I wish appending ;%.2f would cause org-table to display:


| Mass (g) | Mass (lb)     |
|----------+---------------|
| 300 g    | 0.66 lb       |
| 23 kg    | 50.71 lb      |
| 50 Mg    | 110231.13 lb  |
#+TBLFM: $2=uconvert($1, lb);%.2f


If you type in '0.66138679 lb into calc directly, and press d f 2, calc
displays 0.66 lb as desired. Is there any reason for the %.2f notation
chops off the units? Is there some better way to accomplish what I
want?

Thanks!


Note: my spreadsheet uses the wrapper function below to convert units with calc.

#+begin_src emacs-lisp
(defmath uconvert (expression new-units)
    (math-convert-units expression new-units)))
#+end_src

--
Kyle C. Andrews
kyle.c.andrews@gmail.com