How to create the vector 2:10 and 10:2 using the seq function

Question

I need to use seq() to create the vector (2,3,4,5,6,7,8,9,10,9,8,7,6,5,4,3,2), but I'm stuck. I've done quite a bit of YouTube-ing and reading online, but can't find a specific enough solution.

Any help is appreciated, but please use the seq function when making recommendations.

I have provided step-by-step answers for you. Kindly go through it. — Saurabh Chauhan, Feb 03 '17 at 07:33
[You should take care of this](http://stackoverflow.com/help/someone-answers) — Saurabh Chauhan, Feb 04 '17 at 09:34

Saurabh Chauhan · Accepted Answer · 2017-02-03T07:39:02.783

1

Using seq function, you need to following two steps:

Step-1 Generate sequence from 2 to 10 using following code:

a<-seq(from=2,to = 10)

Step-2 Generate sequence from 10 to 2 using following code:

b<-seq(from=9,to = 2)

Now, combine above two results using following code:

data<-c(a,b)

The output should as follow:

> data
[1]  2  3  4  5  6  7  8  9 10  9  8  7  6  5  4  3  2

Hope it works for you!

edited Feb 03 '17 at 07:39

answered Feb 03 '17 at 07:32

Saurabh Chauhan

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score 0 · Answer 2 · answered Feb 03 '17 at 07:35

0

Try this:

unlist(mapply(seq, c(2,9), c(10,2), c(1,-1), SIMPLIFY = FALSE))
#  [1]  2  3  4  5  6  7  8  9 10  9  8  7  6  5  4  3  2

answered Feb 03 '17 at 07:35

Sandipan Dey

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i never downvote @akrun, i have joined SO to learn and share knowledge, not to prove others wrong. – Sandipan Dey Feb 03 '17 at 07:36
also OP wanted to use `seq`. – Sandipan Dey Feb 03 '17 at 08:50

score 0 · Answer 3 · answered Feb 03 '17 at 11:17

According to help(":"),

[...] from:to is equivalent to seq(from, to), and generates a sequence from from to to in steps of 1 or -1.

This is the justification to offer

c(2:10, 9:2)
#[1]  2  3  4  5  6  7  8  9 10  9  8  7  6  5  4  3  2

as solution. Here, seq() is implicitely used but doesn't appear verbatim.

How to create the vector 2:10 and 10:2 using the seq function

3 Answers3