.BG
.VE $Header: /usr3/s/current/s/.help/RCS/seq,v 1.2 83/12/30 19:34:23 rab Exp $
.FN seq
.FN :
.TL
: seq: Sequences
.CS
from:to                    # as operator
seq(from, to, by, length)          # as function
.PP
.AG from
starting value of sequence.
.AG to
ending value of sequence.
.AG by
spacing between successive values in the sequence.
.AG length
number of values in the sequence.
.RT
a numeric vector with values (`from', `from+by',
`from+2*by', ...  `to').  If arguments are omitted,
an appropriate sequence is generated;  for example, with only one
argument a sequence
from `1' to the value of the single argument is constructed.
`from' may be larger or smaller than `to'. 
If it is specified, `by'
must have appropriate sign to generate a finite sequence.
If only `from' is specified, and it is a vector with more than one
value, a sequence from `1' to `len(from)' is generated.
.PP
When used as an operator, `:' has a very high precedence.  Thus to
create a sequence from `1' to `n\-1', parentheses are needed `1:(n\-1)'.
.EX
seq(5) #1,2,3,4,5
1:5 #same thing

5:1 #5,4,3,2,1

seq(0, 1, .01) #0,.01,.02,.03,...,1.

seq(x) # 1, 2, ..., len(x)

seq(\-3.14,3.14,len=100)   # 100 values from \-pi to pi
.KW basic*
.KW builtin
.KW manip
.WR
