The system variable ŒFC contains six characters used by the primitive format function •. The characters are used as follows:
Character Default Usage 1 . Decimal point character 2 , Thousands indicator 3 * Fill for blanks 4 0 Fill for overflows (the default 0 causes a DOMAIN ERROR) 5 _ Print as blank (cannot be ,.0123456789) 6 ¯ Negative number indicator
For details of the way in which ŒFC is used, see the entries for • (Format by Specification and Format by example).