I need this diamond shape pattern in R - r

Question

*
* *
* * *
* * * *
* * * * *
* * * *
* * *
* *
*
This is my code so far, but it throws an error:
Error in " " * (rows - i - 1) : non-numeric argument to binary operator
Calls: pyramid -> print
Execution halted
#R version 3
pyramid<-function(rows){for (i in rows){print(" "*(rows-i-1)+"*"*(i+1))}
for(j in (rows-1|0|-1)){print(" "*(rows-j)+"*"*(j))}}
rows<-5
pyramid(rows)

Answer 1

You can find plenty of (pseudo-code) examples on the net. That should've been your first approach towards solving your problem. SO is not a free code writing service, and you'll get a much more positive response if you demonstrate a genuine attempt at solving the problem yourself.
That aside, here is a "crude" R implementation of a code example I found here. The code can and probably should be "R-ified", and I encourage you to spend some time doing so. I promise that you'll learn a lot. For example, it should be possible to replace most (all?) explicit for loops by making use of vectorised functions.
diamond <- function(max) {
# Upper triangle
space <- max - 1
for (i in 0:(max - 1)) {
for (j in 0:space) cat(" ")
for (j in 0:i) cat("* ")
cat("\n")
space <- space - 1
}
# Lower triangle
space = 1;
for (i in (max - 1):1) {
for (j in 0:space) cat(" ")
for (j in 0:(i - 1)) cat("* ")
cat("\n")
space <- space + 1
}
}
diamond(5)
# *
# * *
# * * *
# * * * *
#* * * * *
# * * * *
# * * *
# * *
# *