What I remember from my Data Science skills interviews - Part 1

As someone who wants to be more comfortable doing skills tests, I find myself applying to jobs sometimes for the sole purpose of having a feel of the test and challenging myself to complete it on time. On some occasions I really do well and on some I am left thinking "I wish there was no pressure to complete this test in the given time". 

I would also note that the example below is not an exact replica of any test I have done. 

#A FUNCTION THAT CHECKS IF A WORD(S) IS A PALINDROME

(The Code is in R)

palindrome_check = function(k){

  k <- tolower(gsub(" ","",k))

  newname <- c()

  for (i in 1:nchar(k)) {

    newname[i] <- (unlist(strsplit(k, split = "")))[nchar(k)-(i-1)]

  }

  k_new <- paste(newname, collapse  =  "")

  ifelse(k_new == k, "This is a palindrome", "This is not a palindrome")

}

Examples

palindrome_check("civic")

Result: "This is a palindrome"

palindrome_check("mother")

Result: "This is not a palindrome"

palindrome_check("bird rib")

Result: "This is a palindrome"

palindrome_check("Kayak")

Result: "This is a palindrome"

Breakdown

gsub() is used to find any spaces and remove them. str_remove_all can be used here too.

tolower() is used to deal with an exception that may rise since R is case sensitive.

There are easier ways to reverse the order of characters in a string like: 

Using the function rev()

string_example <- "civic"

paste(rev(unlist(strsplit(string_example, split = ""))), collapse  = "")

Breakdown

#split the string by characters

strsplit(string_example, split = "") 

•  The result is a list and we need to undo that using the unlist() function.

#Unlist split characters

unlist(...)

#Reverse the order of the characters

rev(...)

#Bind the characters together

paste(..., collapse = "")

Happy exploring!!

~NMN