Legacy Document

+

You can use the + symbol to add two real numbers.

x + y

x

Any floating-point number.

y

Any floating-point number.

DESCRIPTION

The + operator performs the standard addition of two floating-point numbers.

EXCEPTIONS

When x and y are both finite and nonzero, either the result of x + y is exact or it raises one of the following exceptions:

• inexact (if the result must be rounded or if an overflow or underflow occurs)
• overflow (if the result is outside the range of the data type)
• underflow (if the result is inexact and must be represented as a denormalized number or 0)

SPECIAL CASES

Table 6-3 shows the results when one of the operands of the addition operation is a zero, a NaN, or an Infinity. In this table, x is any floating-point number.

Table 6-3 Special cases for floating-point addition

Operation	Result	Exceptions raised
$x+(+0)$	x	None
$x+(-0)$	x	None
$(-0)+(+0)$	+0	None
$(-0)+(-0)$	$-0$	None
$x+NaN$	NaN	None[5]
$x+(+$ )	+	None
$x+(-$ )	$-$	None
$+$ +(- )	NaN	Invalid

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[5] If the NaN is a signaling NaN, the invalid exception is raised.