The NOT Gate emits the complement of whatever input it receives. The truth table for a NOT gate is the following.
If the input is unspecified (i.e., floating), then the output will also be unspecified - unless the "Gate Output When Undefined" option is "Error for undefined inputs," in which case the output is an error. If the input is an error value, then the output will also be.
A multi-bit NOT gate will perform the above transformation bitwise on its input.
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