R help - Jun 2006 - probably need to se sapply but i can't get it

Hi : I think I need to use sapply but I can't figure this out.

Suppose I have two vectors : tempa ( 4, 6,10 ) and  tempb 
(  11,23 ,39 ) 


I want a function that returns 4:11,6:23 and 10:39 as vectors.

I tried :

sapply(1:length(tempa) function (z) seq(tempa[z],tempb[z])

but i got 3 really strange vectors back in the sense that the numbers in them
did not make no sense to me. obviously,
i must be doing something wrong.  thanks a lot.

                                       mark

On Mon, 2006-06-26 at 12:40 -0500, markleeds at verizon.net
wrote:
> Hi : I think I need to use sapply but I can't figure this out.
> 
> Suppose I have two vectors : tempa ( 4, 6,10 ) and  tempb 
> (  11,23 ,39 ) 
> 
> 
> I want a function that returns 4:11,6:23 and 10:39 as vectors.
> 
> I tried :
> 
> sapply(1:length(tempa) function (z) seq(tempa[z],tempb[z])
> 
> but i got 3 really strange vectors back in the sense that the numbers
> in them did not make no sense to me. obviously,
> i must be doing something wrong.  thanks a lot.
> 
>                                        mark

Mark,

Try this using mapply():

 tempa <- c(4, 6, 10)

 tempb <- c(11, 23, 39)

> mapply(seq, from = tempa, to = tempb)
[[1]]
[1]  4  5  6  7  8  9 10 11

[[2]]
 [1]  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

[[3]]
 [1] 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
[23] 32 33 34 35 36 37 38 39


You will get a list back in this case and you can then deal with the 3
vectors as you require. Each vector is a different length, so a list is
about the only way to return them here.

See ?mapply for more info.

HTH,

Marc Schwartz

On Mon, 26 Jun 2006, markleeds at verizon.net wrote:
> Hi : I think I need to use sapply but I can't figure this out.
>
> Suppose I have two vectors : tempa ( 4, 6,10 ) and  tempb
> (  11,23 ,39 )
>
>
> I want a function that returns 4:11,6:23 and 10:39 as vectors.
>
> I tried :
>
> sapply(1:length(tempa) function (z) seq(tempa[z],tempb[z])
>
> but i got 3 really strange vectors back in the sense that the numbers in
them did not make no sense to me. obviously,
> i must be doing something wrong.  thanks a lot.
An easier way to do this is
   mapply(seq,tempa,tempb)

Your approach should have worked. It's hard to tell why it didn't
because
there are two syntax errors in your example so it clearly isn't actually 
what you did.  Fixing them, I get
> sapply(1:length(tempa), function (z) seq(tempa[z],tempb[z]))
[[1]]
[1]  4  5  6  7  8  9 10 11

[[2]]
  [1]  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

[[3]]
  [1] 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
[26] 35 36 37 38 39

as you wanted.

 	-thomas