The Trabb Pardo–Knuth algorithm.

trabb_pardo_knuth.ps1

#
# Trabb Pardo–Knuth algorithm
#
# see http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
#


function TPK_function($x)
{
  return [math]::pow([math]::abs($x), .5) + 5 * [math]::pow($x, 3)
}


function TPK([string] $f)
{
  [double[]] $values
    
  # ask for 11 numbers to be read into a sequence S
  Write-Host "Please enter 11 numbers"
  1..11 |% { $values += @(Read-Host $_) }
    
  # for each item in sequence S
  1..11 |% {
    # reverse sequence S
    $v = $values[11-$_]
    # result := call a function to do an operation
    $result = Invoke-Expression "$f $v"
    if ($result -gt 400) {
      # if result overflows alert user!
      Write-Error "Result too large!"
    } else {
      # print result
      Write-Host "f($v) = $result"
    }
  }
}


TPK "TPK_function"