if ( !preg_match( '/^\d{1,4}$/', $_ ) ) {
return strrev( (string)preg_replace( '/(\d{3})(?=\d)(?!\d*\.)/', '$1,', strrev( $_ ) ) );
} else {
if ( !preg_match( '/^\d{1,4}$/', $_ ) ) {
return strrev( (string)preg_replace( '/(\d{3})(?=\d)(?!\d*\.)/', '$1,', strrev( $_ ) ) );
} else {