GAP Manual: 10.4. RemInt

RemInt( n1, n2 )

RemInt returns the remainder of its two integer operands.

If n2 is not equal to zero RemInt( n1, n2 ) = n1 - n2* QuoInt( n1, n2 ). Note that the rules given for QuoInt (see QuoInt) imply that RemInt( n1, n2 ) has the same sign as n1 and its absolute value is strictly less than the absolute value of n2. Dividing by 0 signals an error.

    gap> RemInt(5,2);  RemInt(-5,2);  RemInt(5,-2);  RemInt(-5,-2);
    1
    -1
    1
    -1