What is the alternate to 'in' command we have in Python, for R?

Question

Say I have a numerical vector in R. And I want to see if a particular integer is present in the vector or not. We can do that easily in python using 'in' command and an if statement may be.

Do we have something similar in R as well? So that I don't have to use a for loop to check if the integer I want is present in a vector? I tried the following, but it does not seem to work. 'normal' is a dataframe and the second column has integers.

if (12069692 in normal[,2]) {print("yes")}

Says,

Error: unexpected 'in' in "if (12069692 in"

I'm sorry, but -1 for a lack of research effort. If I google *R find value in vector*, first hit is, I believe, a [duplicate of this question](http://stackoverflow.com/q/1169248/1478381) — Simon O'Hanlon, Apr 11 '13 at 16:22

NPE · Accepted Answer · 2013-04-11T15:59:02.247

5

In R, it's called %in%:

> 1 %in% c(1, 2, 3)
[1] TRUE
> 4 %in% c(1, 2, 3)
[1] FALSE

It is vectorized on the left-hand side, so you can check multiple values at once:

> c(1, 4, 2, 1) %in% c(1, 2, 3)
[1]  TRUE FALSE  TRUE  TRUE

(hat tip @Spacedman)

edited Apr 11 '13 at 15:59

answered Apr 11 '13 at 15:48

NPE

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Ah! That was simple. This %in% datatype was always hard for me to understand. Thanks! – Jordan Apr 11 '13 at 15:51
2

And its vectorised on the LHS: `c(1,2,4,5) %in% c(1, 2, 3)` is `TRUE TRUE FALSE FALSE`. – Spacedman Apr 11 '13 at 15:51
I voted to close the question as duplicate, but +1 for the useful answer. – Simon O'Hanlon Apr 11 '13 at 16:23

What is the alternate to 'in' command we have in Python, for R?

1 Answers1