Change Currency Symbol

We needed to use NZ$ instead of $ for pricing which was achieved by adding the following to THEME/functions.php

// change currency symbol
add_filter('woocommerce_currency_symbol', 'change_existing_currency_symbol', 10, 2);

function change_existing_currency_symbol( $currency_symbol, $currency ) {
     switch( $currency ) {
          case 'NZD': $currency_symbol = 'NZ$'; break;
     }
     return $currency_symbol;
}