R help - Mar 2010 - How to use "ifelse" to generate random value from a distribution

I need use different parameters of distribution for different case to
generate random value, but I use ifelse, the generated value is fixed
without change. 
Here is  example
data1
    y x
1   1 2
2   2 1
3   3 2
4   4 3
5   5 3
6   6 1
7   7 2
8   8 1
9   9 1
10 10 3
11 11 3
12 12 2
ifelse(data1$x==1,rnorm(1,2,1),ifelse(data1$x==2,rnorm(1,-2,1),rnorm(1,110,1)))
 [1]  -1.8042172   0.8478681  -1.8042172 110.0301239 110.0301239   0.8478681 
-1.8042172   0.8478681   0.8478681 110.0301239
[11] 110.0301239  -1.8042172

How can I get real random value from a distribution. Thanks.
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I think I figure it out.

ifelse(data1$x==1,rnorm(12,2,1),ifelse(data1$x==2,rnorm(12,-2,1),rnorm(12,110,1)))

Please correct me if  I am wrong.  Thanks
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alex46015 wrote:
> I think I figure it out.
> 
>
ifelse(data1$x==1,rnorm(12,2,1),ifelse(data1$x==2,rnorm(12,-2,1),rnorm(12,110,1)))
> 

Where is the number 12 coming from? Is that the length of data1$x?


Here is a sample using the fact that rnorm can accept vectors of means 
and sds.   My x is randomly generated since you did not provide a 
reproducible example.

#random data, can take on 3 values

x <- sample(1:3, 100, replace = TRUE)

#i tried to make this identical to your criteria

mns <- ifelse(x == 1, 2, ifelse(x==2, -2, 110))

#use vectors!, do not hardcode length(x)!

rnorm(length(x), mns)


HTH,
--Erik