check without loop

I think the which() function would be helpful.  For example if x is a

and c some value then

which( x == c )

will return a vector of those indices i of x for which x[i] = c.  Then you
can test whether that vector
has length 0.

-----Original Message-----
From: jimi adams [SMTP:imij at columbus.rr.com]
Sent: Wednesday, March 20, 2002 11:41 AM
To: r-help at stat.math.ethz.ch
Subject: [R] check without loop

i am probably just missing this one, but how can i check to see if a
number
is a part of a vector?

i know i could do a loop checking for equivalence for each element, but

am
thinking that there must be a simpler way to do it than that ( i think
that
i have even done it in the past, but can't remember how!)
thanks

what i am working with:
(hope this makes sense)

arclist
  [1]   2   2   6   7   8   9   9  11  11  11  12  13  14  15  16  17

21
 [19]  22  23  24  25  25  29  29  30  32  34  35  35  38  39  40  40

42
 [37]  43  44  45  46  47  48  49  50  51  52  53  54  57  58  59  60

61
 [55]  61  61  61  61  61  61  61  61  61  61  61  61  61  61  61  61

61
 [73]  61  61  61  61  61  61  61  61  61  61  62  65  67  68  68  69

72
 [91]  75  76  77  79  81  82  83  84  84  85  86  87  88  90  91  92

94
[109]  95  96  96  96  96 100

# and am sampling from a different list
# if i draw, say 80, i would then not want to proceed, but if i draw a
number on arclist i do



jimi adams
Department of Sociology
The Ohio State University
300 Bricker Hall
190 N Oval Mall
Columbus, OH 43210-1353
614-688-4261

our mind has a remarkable ability to think of contents as being
independent
of the act of thinking
                                            -georg simmel

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