Topic: DMD0536
Math Negate Operator
The Math Negate operator ( - ) returns the same value with the opposite sign.
The operand can be any mix of signed integers, unsigned integers, real (floating point) numbers or discrete values. They can be any numeric or discrete memory location, or any numeric or discrete structure member.
All discrete values and all 16-bit integer values are promoted to 32-bit 2's complement signed integer values. If a Real value is included in the equation then all of the values will be promoted to Real values and all calculations will be performed using Real numbers.
Traditional math precedence rules are used to solve the math expression, The use of parentheses to remove any ambiguity in the processing order is encouraged.
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assume D0 = 123456789 and D1 = -123456789 and R1 = 1234567.890 and X0 = ON
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D0 = -D0
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D0 = - (123456789) D0 = -123456789
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The operand is a signed integer memory location.
The result is placed in a signed integer memory location.
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D0 = -D1
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D0 = - (-123456789) D0 = 123456789
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The operand is a signed integer memory location.
The result is placed in a signed integer memory location.
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R0 = -R1
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R0 = - (1234567.890) R0 = -1234567.890
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The operand is a Real memory location.
The result is placed in a Real memory location.
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C0 = -X0
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C0 = - ( 0000_0000_0000_00001 ) C0 = 1111_1111_1111_1111 C0 = ON
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The operand is a discrete memory location.
X0 is promoted to32-bit 2’s complement equivalent of 1. Negating it gives you -1, which in terms of a numeric compare, is still ON (non-zero).
The result is placed in a discrete memory location.
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See Also:
Negate
Related Topics: