HAMMING_DISTANCE

HAMMING_DISTANCE(vector1, vector2);

Description

Computes the Hamming Distance between two vectors of equal length. Hamming distance is the number of positions at which the corresponding elements of two equal-length strings/vectors are different.

Parameter Description

• vector1: The first vector, supported type vector\<tinyint>
• vector2: The second vector, supported type vector\<tinyint>

Note: Both vectors must have the same length.

Return Result

Returns a bigint value representing the number of positions where elements differ between the two vectors.

Examples

• Compute the Hamming distance between two vector\<tinyint> vectors

SELECT HAMMING_DISTANCE(VECTOR(1y, 0y, 1y), VECTOR(1y, 1y, 0y)) as hamming_dis;
+-------------+
| hamming_dis |
+-------------+
| 2           |
+-------------+

• Compute the Hamming distance between longer tinyint vectors

SELECT HAMMING_DISTANCE(VECTOR(1y, 0y, 1y, 0y), VECTOR(1y, 0y, 0y, 1y)) as hamming_dis;
+-------------+
| hamming_dis |
+-------------+
| 2           |
+-------------+

• Compute the Hamming distance between identical vectors (result is 0)

SELECT HAMMING_DISTANCE(VECTOR(1y, 1y, 0y), VECTOR(1y, 1y, 0y)) as hamming_dis;
+-------------+
| hamming_dis |
+-------------+
| 0           |
+-------------+