Stibitz code
| Stibitz code | |
|---|---|
| Number of digits | 4th |
| assessable | No |
| steadily | No |
| Weight | 0..4 |
| Minimum distance | 1 |
| Maximum distance | 4th |
| Hamming distance | 1 |
| redundancy | 0.7 |
| Decimal digit |
Stibitz- coded |
BCD coded |
Binary coded |
|---|---|---|---|
| 0 | 0 0 1 1 | 0 0 0 0 | 0 0 0 0 |
| 1 | 0 1 0 0 | 0 0 0 1 | 0 0 0 1 |
| 2 | 0 1 0 1 | 0 0 1 0 | 0 0 1 0 |
| 3 | 0 1 1 0 | 0 0 1 1 | 0 0 1 1 |
| 4th | 0 1 1 1 | 0 1 0 0 | 0 1 0 0 |
| 5 | 1 0 0 0 | 0 1 0 1 | 0 1 0 1 |
| 6th | 1 0 0 1 | 0 1 1 0 | 0 1 1 0 |
| 7th | 1 0 1 0 | 0 1 1 1 | 0 1 1 1 |
| 8th | 1 0 1 1 | 1 0 0 0 | 1 0 0 0 |
| 9 | 1 1 0 0 | 1 0 0 1 | 1 0 0 1 |
The Stibitz code or excess -3- or excess-3 code is a by George Stibitz named complementary BCD - Code . The decimal digits from 0 to 9 are assigned a 4- bit tetrad according to the following table .
This code is obtained by adding 2 (= 3 10 ) to each tetrad of the BCD code 0011 .
properties
The advantage of the Stibitz code is that the nine's complement - the generalization of the one's complement of binary numbers - of a digit-coded decimal number can be produced very easily: only all zeros have to be replaced by ones and all ones by zeros, i.e. it is sufficient to to compute the bitwise logical complement. This makes it easier to calculate with negative numbers.
The tetrads 0000, 0001, 0010, 1101, 1110 and 1111 do not occur. These are called pseudo-tetrads .
