The arithmetic operators take numeric operands and produce numeric results.
a + b
Yields the sum of a and b.
a - b
Subtracts b from a and yields the difference.
a * b
Yields the product of a and b. If either a or b is 0, then the result is 0, even if the other operand is missing.
a / b
Divides a by b and yields the quotient. If a is 0, then the result is 0, even if b is missing. If b is zero, the result is system-missing.
a ** b
Yields the result of raising a to the power b. If
a is negative and b is not an integer, the result is
system-missing. The result of
0**0 is system-missing as well.
Reverses the sign of a.