Fixed-Point Blockset

Signed Fixed-Point Numbers

Computer hardware typically represents the negation of a binary fixed-point number in three different ways: sign/magnitude, one's complement, and two's complement. Two's complement is the preferred representation of signed fixed-point numbers and is supported by the Fixed-Point Blockset.

Negation using two's complement consists of a bit inversion (translation into one's complement) followed by the addition of a one. For example, the two's complement of 000101 is 111011.

Whether a fixed-point value is signed or unsigned is usually not encoded explicitly within the binary word (i.e., there is no sign bit). Instead, the sign information is implicitly defined within the computer architecture.

Fixed-Point Numbers

Radix Point Interpretation