fneg

fneg

Forms fneg = 118 (0x76)

Stack ..., value ..., result

Description The value must be of type float. It is popped from the operand stack. The float result is the arithmetic negation of value, -value. The result is pushed onto the operand stack.

For float values, negation is not the same as subtraction from zero. If x is +0.0, then 0.0-x equals +0.0, but -x equals -0.0. Unary minus merely inverts the sign of a float.

Special cases of interest:

• If the operand is NaN, the result is NaN (recall that NaN has no sign).
• If the operand is an infinity, the result is the infinity of opposite sign.
• If the operand is a zero, the result is the zero of opposite sign.