PHP-Code

<?php

require_once('InitialsGenerator.php');

array_shift($argv); // remove script name

if (sizeof($argv) !== 1) {
  die ('ERROR: 1 parameter needed, ' . sizeof($argv) . ' provided.' . PHP_EOL);
}

$name = $argv[0];
$initials1 = InitialsGenerator::getInitials_1($name);
$initials2 = InitialsGenerator::getInitials_2($name);
$initials3a = InitialsGenerator::getInitials_3a($name);
$initials3b = InitialsGenerator::getInitials_3b($name);

echo 'NAME        : "' , $name , '"' , PHP_EOL;
echo 'INITIALS 1  : "' , $initials1 , '"' , PHP_EOL;
echo 'INITIALS 2  : "' , $initials2 , '"' , PHP_EOL;
echo 'INITIALS 3a : "' , $initials3a , '"' , PHP_EOL;
echo 'INITIALS 3b : "' , $initials3b , '"' , PHP_EOL;

PHP-Code

<?php

final class InitialsGenerator
{
  private function __construct() { }

  private static function getMatches(string $pattern, string $subject): array
  {
    preg_match_all($pattern, $subject, $matches);
    return $matches[0];
  }

  /**
  * Get the initials with upper- and lowercase characters mixed.
  * Also without slashes.
  */
  public static function getInitials_1(string $name): string 
  {
    return implode('', self::getMatches('/\b[A-Za-z]/', $name));
  } 

  /**
  * Get the initials with upper- and lowercase characters mixed.
  * But this time with slashes.
  */
  public static function getInitials_2(string $name): string 
  {
    return implode('', self::getMatches('/\b[A-Za-z\-]/', $name));
  } 

  /**
  * Get the initials with only uppercase characters.
  * Also without slashes.
  */
  public static function getInitials_3a(string $name): string 
  {
    return strtoupper(self::getInitials_1($name));
  }

  /**
  * Get the initials with uppercase characters.
  * But this time with slashes.
  */
  public static function getInitials_3b(string $name): string 
  {
    return strtoupper(self::getInitials_2($name));
  }
}