Hi Cecil
On Sun, Jun 1, 2014 at 2:24 PM, Cecil Westerhof <cldwester...@gmail.com> wrote:
> But what if I would want to know the
> difference between the previous filled one, divided by the distance?
>
> For example:
> |-------+------------|
> | value | difference |
> |-------+------------|
> | 12 | |
> | 15 | 3 |
> | | |
> | 83 | 34 |
> | | |
> | | |
> | | |
> | 87 | 1 |
> | | |
> | | |
> | | |
> | 85 | -0.5 |
> | | |
> |-------+------------|
More as a demonstration of what Calc can do, divided up into some
intermediate steps:
|-------+---------------------------------------------------------|
| value | difference |
|-------+---------------------------------------------------------|
| 12 | |
| 15 | [15, 12] |
| | |
| 83 | [83, nan, 15, 12] |
| | |
| | |
| | |
| 87 | [87, nan, nan, nan, 83, nan, 15, 12] |
| | |
| | |
| | |
| 85 | [85, nan, nan, nan, 87, nan, nan, nan, 83, nan, 15, 12] |
| | |
|-------+---------------------------------------------------------|
#+TBLFM: $2 = if(vlen(@-I$1..@0$1) == 1 || "$1" == "nan", string(""),
rev(@-I$1..@0$1)); E
|-------+----------------------------------------------------|
| value | difference |
|-------+----------------------------------------------------|
| 12 | |
| 15 | [0, 0] |
| | |
| 83 | [0, nan, 0, 0] |
| | |
| | |
| | |
| 87 | [0, nan, nan, nan, 0, nan, 0, 0] |
| | |
| | |
| | |
| 85 | [0, nan, nan, nan, 0, nan, nan, nan, 0, nan, 0, 0] |
| | |
|-------+----------------------------------------------------|
#+TBLFM: $2 = if(vlen(@-I$1..@0$1) == 1 || "$1" == "nan", string(""),
0 * rev(@-I$1..@0$1)); E
Distance to previous element:
|-------+------------|
| value | difference |
|-------+------------|
| 12 | |
| 15 | 1 |
| | |
| 83 | 2 |
| | |
| | |
| | |
| 87 | 4 |
| | |
| | |
| | |
| 85 | 4 |
| | |
|-------+------------|
#+TBLFM: $2 = if(vlen(@-I$1..@0$1) == 1 || "$1" == "nan", string(""),
find(0 * rev(@-I$1..@0$1), 0, 2) - 1); E
Previous element:
|-------+------------|
| value | difference |
|-------+------------|
| 12 | |
| 15 | 12 |
| | |
| 83 | 15 |
| | |
| | |
| | |
| 87 | 83 |
| | |
| | |
| | |
| 85 | 87 |
| | |
|-------+------------|
#+TBLFM: $2 = if(vlen(@-I$1..@0$1) == 1 || "$1" == "nan", string(""),
subscr(rev(@-I$1..@0$1), find(0 * rev(@-I$1..@0$1), 0, 2)); E
Combined:
|-------+------------|
| value | difference |
|-------+------------|
| 12 | |
| 15 | 3 |
| | |
| 83 | 34 |
| | |
| | |
| | |
| 87 | 1 |
| | |
| | |
| | |
| 85 | -0.5 |
| | |
|-------+------------|
#+TBLFM: $2 = if(vlen(@-I$1..@0$1) == 1 || "$1" == "nan", string(""),
($1 - subscr(rev(@-I$1..@0$1), find(0 * rev(@-I$1..@0$1), 0, 2))) /
(find(0 * rev(@-I$1..@0$1), 0, 2) - 1)); E
For many here on the list it would probably be easier and more
interesting to write a TBLFM in Lisp.
Michael
