$WOOCS->get_currency_price_num_decimals()

Returns count of decimals for any currency code which is defined on the plugin settings page

global $WOOCS;
$currency = $WOOCS->get_currency_price_num_decimals($currency);

$currency - is any currency code, for example 'EUR'

Shortcodes, functions, actions and filters reference for FOX WooCommerce Currency Switcher