Question

I'm using the programming language R. Can someone please tell me why this returns true?

a1=c(5,"7",9,12,"15")
a2=c(5,7,9,12,15)

a1 == a2

Output is:

> a1 == a2
[1] TRUE TRUE TRUE TRUE TRUE

Answer 1

a1=c(5,"7",9,12,"15")

Here all are considered as characters so the characters are 5 7 9 12 15 irrespective of quotation.

a2=c(5,7,9,12,15)

Here the characters are 5 7 9 12 15

a1 == a2

Here we are compare every character of a1 with a2

5 == 5 ---------->TRUE

7 == 7 ---------->TRUE

9 == 9 ---------->TRUE

12 == 12 ------->TRUE

15 == 15 ------->TRUE

So it print as

a1 == a2
[1] TRUE TRUE TRUE TRUE TRUE