[R] combination which limited

[Marc Schwartz]

On Sat, 2005-06-11 at 20:44 +0200, Muhammad Subianto wrote:
> Dear R-helpers,
> I am learning about combination in R.
> I want to combination all of
> possible variable but it limited. 
> I am sorry I could not explain exactly.
> For usefull I give an example
>   interface <- c("usb","fireware","infra","bluetooth")
>   screen    <- c("lcd","cube")
>   computer  <- c("pc","server","laptop")
>   available <- c("yes","no")
>   
> What the result I need, something like this below,
>   usb          lcd     pc      yes
>   fireware     lcd     pc      yes
>   infra        lcd     pc      yes
>   bluetooth    lcd     pc      yes
>   usb          cube    pc      yes 
>   usb          lcd     server  yes
>   usb          lcd     laptop  yes
>   usb          lcd     pc      no
>   
> How can I do that?
> I was wondering if someone can help me.
> Thanks you for your time and best regards,
> Muhammad Subianto

Use:

> expand.grid(interface, screen, computer, available)
        Var1 Var2   Var3 Var4
1        usb  lcd     pc  yes
2   fireware  lcd     pc  yes
3      infra  lcd     pc  yes
4  bluetooth  lcd     pc  yes
5        usb cube     pc  yes
6   fireware cube     pc  yes
7      infra cube     pc  yes
8  bluetooth cube     pc  yes
9        usb  lcd server  yes
10  fireware  lcd server  yes
11     infra  lcd server  yes
12 bluetooth  lcd server  yes
13       usb cube server  yes
14  fireware cube server  yes
15     infra cube server  yes
16 bluetooth cube server  yes
17       usb  lcd laptop  yes
18  fireware  lcd laptop  yes
19     infra  lcd laptop  yes
20 bluetooth  lcd laptop  yes
21       usb cube laptop  yes
22  fireware cube laptop  yes
23     infra cube laptop  yes
24 bluetooth cube laptop  yes
25       usb  lcd     pc   no
26  fireware  lcd     pc   no
27     infra  lcd     pc   no
28 bluetooth  lcd     pc   no
29       usb cube     pc   no
30  fireware cube     pc   no
31     infra cube     pc   no
32 bluetooth cube     pc   no
33       usb  lcd server   no
34  fireware  lcd server   no
35     infra  lcd server   no
36 bluetooth  lcd server   no
37       usb cube server   no
38  fireware cube server   no
39     infra cube server   no
40 bluetooth cube server   no
41       usb  lcd laptop   no
42  fireware  lcd laptop   no
43     infra  lcd laptop   no
44 bluetooth  lcd laptop   no
45       usb cube laptop   no
46  fireware cube laptop   no
47     infra cube laptop   no
48 bluetooth cube laptop   no


See ?expand.grid for more information.

Using:

> help.search("combinations")

would guide you to that function based upon a keyword search.

HTH,

Marc Schwartz