Re: How modify numbers in a region by a multiplier?

[Dan Davison]

Juanma Barranquero <lekktu@gmail.com> writes:

> On Thu, Jul 1, 2010 at 15:55, Seweryn Kokot <sewkokot@gmail.com> wrote:
>
>> Imagine that I have some numbers
>>
>> 33.444 3333 4433.4443 3344 .34234
>>
>> and I want them multiplied for example by 0.1
>>
>> to receive
>>
>> 3.3444 333.3 443.34443 334.4 .034234

Here are three solutions using Org-mode.

* Using the Org spreadsheet
http://orgmode.org/org.html#The-spreadsheet
http://orgmode.org/worg/org-tutorials/org-spreadsheet-intro.php

Leave second column blank; issue C-u C-c C-c with point in the table 

|    33.444 |    3.3444 |
|      3333 |     333.3 |
| 4433.4443 | 443.34443 |
|      3344 |     334.4 |
|   0.34234 |  0.034234 |
#+tblfm: $2=$1*0.1


* Using Org-babel
http://orgmode.org/worg/org-contrib/babel/index.php
Unless using Org from git it's in the Org contrib directory; Org-babel
is integrated into Org in the git HEAD and so in the next Org release,
with a new manual chapter.

Use C-c C-c on the source code blocks to generate the results tables.

#+tblname: tab
| 33.444 | 3333 | 4433.4443 | 3344 | .34234 |

** Using emacs lisp

#+begin_src emacs-lisp :var X=tab
(mapcar (lambda (x) (* 0.1 x)) (car X))
#+end_src

#+results:
| 3.3444000000000003 | 333.3 | 443.34443000000005 | 334.40000000000003 | 
0.034234 |

** Using R
#+begin_src R :var X=tab
X * 0.1
#+end_src

#+results:
| 3.3444 | 333.3 | 443.34443 | 334.4 | 0.034234 |


Dan


>
> Interactively, you can try with some variation of
>
> M-x replace-regexp \([0-9.]+\) <RET> \,(/ (string-to-number \1) 10.0) <RET>
>
>     Juanma