ClickHouse/docs/en/sql-reference/functions/distance-functions.md

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---
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slug: /en/sql-reference/functions/distance-functions
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sidebar_position: 55
sidebar_label: Distance
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---
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# Distance Functions
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## L1Norm
Calculates the sum of absolute values of a vector.
**Syntax**
```sql
L1Norm(vector)
```
Alias: `normL1`.
**Arguments**
- `vector` — [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
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**Returned value**
- L1-norm or [taxicab geometry](https://en.wikipedia.org/wiki/Taxicab_geometry) distance.
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Type: [UInt](../../sql-reference/data-types/int-uint.md), [Float](../../sql-reference/data-types/float.md) or [Decimal](../../sql-reference/data-types/decimal.md).
**Examples**
Query:
```sql
SELECT L1Norm((1, 2));
```
Result:
```text
┌─L1Norm((1, 2))─┐
│ 3 │
└────────────────┘
```
## L2Norm
Calculates the square root of the sum of the squares of the vector values.
**Syntax**
```sql
L2Norm(vector)
```
Alias: `normL2`.
**Arguments**
- `vector` — [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
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**Returned value**
- L2-norm or [Euclidean distance](https://en.wikipedia.org/wiki/Euclidean_distance).
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Type: [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT L2Norm((1, 2));
```
Result:
```text
┌───L2Norm((1, 2))─┐
│ 2.23606797749979 │
└──────────────────┘
```
## LinfNorm
Calculates the maximum of absolute values of a vector.
**Syntax**
```sql
LinfNorm(vector)
```
Alias: `normLinf`.
**Arguments**
- `vector` — [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
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**Returned value**
- Linf-norm or the maximum absolute value.
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Type: [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT LinfNorm((1, -2));
```
Result:
```text
┌─LinfNorm((1, -2))─┐
│ 2 │
└───────────────────┘
```
## LpNorm
Calculates the root of `p`-th power of the sum of the absolute values of a vector in the power of `p`.
**Syntax**
```sql
LpNorm(vector, p)
```
Alias: `normLp`.
**Arguments**
- `vector` — [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
- `p` — The power. Possible values: real number in `[1; inf)`. [UInt](../../sql-reference/data-types/int-uint.md) or [Float](../../sql-reference/data-types/float.md).
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**Returned value**
- [Lp-norm](https://en.wikipedia.org/wiki/Norm_(mathematics)#p-norm)
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Type: [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT LpNorm((1, -2), 2);
```
Result:
```text
┌─LpNorm((1, -2), 2)─┐
│ 2.23606797749979 │
└────────────────────┘
```
## L1Distance
Calculates the distance between two points (the values of the vectors are the coordinates) in `L1` space (1-norm ([taxicab geometry](https://en.wikipedia.org/wiki/Taxicab_geometry) distance)).
**Syntax**
```sql
L1Distance(vector1, vector2)
```
Alias: `distanceL1`.
**Arguments**
- `vector1` — First vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
- `vector2` — Second vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
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**Returned value**
- 1-norm distance.
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Type: [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT L1Distance((1, 2), (2, 3));
```
Result:
```text
┌─L1Distance((1, 2), (2, 3))─┐
│ 2 │
└────────────────────────────┘
```
## L2Distance
Calculates the distance between two points (the values of the vectors are the coordinates) in Euclidean space ([Euclidean distance](https://en.wikipedia.org/wiki/Euclidean_distance)).
**Syntax**
```sql
L2Distance(vector1, vector2)
```
Alias: `distanceL2`.
**Arguments**
- `vector1` — First vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
- `vector2` — Second vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
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**Returned value**
- 2-norm distance.
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Type: [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT L2Distance((1, 2), (2, 3));
```
Result:
```text
┌─L2Distance((1, 2), (2, 3))─┐
│ 1.4142135623730951 │
└────────────────────────────┘
```
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## L2SquaredDistance
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Calculates the sum of the squares of the difference between the corresponding elements of two vectors.
**Syntax**
```sql
L2SquaredDistance(vector1, vector2)
```
Alias: `distanceL2Squared`.
**Arguments**
- `vector1` — First vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
- `vector2` — Second vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
**Returned value**
Type: [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT L2SquaredDistance([1, 2, 3], [0, 0, 0])
```
Result:
```response
┌─L2SquaredDistance([1, 2, 3], [0, 0, 0])─┐
│ 14 │
└─────────────────────────────────────────┘
```
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## LinfDistance
Calculates the distance between two points (the values of the vectors are the coordinates) in `L_{inf}` space ([maximum norm](https://en.wikipedia.org/wiki/Norm_(mathematics)#Maximum_norm_(special_case_of:_infinity_norm,_uniform_norm,_or_supremum_norm))).
**Syntax**
```sql
LinfDistance(vector1, vector2)
```
Alias: `distanceLinf`.
**Arguments**
- `vector1` — First vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
- `vector1` — Second vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
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**Returned value**
- Infinity-norm distance.
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Type: [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT LinfDistance((1, 2), (2, 3));
```
Result:
```text
┌─LinfDistance((1, 2), (2, 3))─┐
│ 1 │
└──────────────────────────────┘
```
## LpDistance
Calculates the distance between two points (the values of the vectors are the coordinates) in `Lp` space ([p-norm distance](https://en.wikipedia.org/wiki/Norm_(mathematics)#p-norm)).
**Syntax**
```sql
LpDistance(vector1, vector2, p)
```
Alias: `distanceLp`.
**Arguments**
- `vector1` — First vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
- `vector2` — Second vector. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
- `p` — The power. Possible values: real number from `[1; inf)`. [UInt](../../sql-reference/data-types/int-uint.md) or [Float](../../sql-reference/data-types/float.md).
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**Returned value**
- p-norm distance.
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Type: [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT LpDistance((1, 2), (2, 3), 3);
```
Result:
```text
┌─LpDistance((1, 2), (2, 3), 3)─┐
│ 1.2599210498948732 │
└───────────────────────────────┘
```
## L1Normalize
Calculates the unit vector of a given vector (the values of the tuple are the coordinates) in `L1` space ([taxicab geometry](https://en.wikipedia.org/wiki/Taxicab_geometry)).
**Syntax**
```sql
L1Normalize(tuple)
```
Alias: `normalizeL1`.
**Arguments**
- `tuple` — [Tuple](../../sql-reference/data-types/tuple.md).
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**Returned value**
- Unit vector.
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Type: [Tuple](../../sql-reference/data-types/tuple.md) of [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT L1Normalize((1, 2));
```
Result:
```text
┌─L1Normalize((1, 2))─────────────────────┐
│ (0.3333333333333333,0.6666666666666666) │
└─────────────────────────────────────────┘
```
## L2Normalize
Calculates the unit vector of a given vector (the values of the tuple are the coordinates) in Euclidean space (using [Euclidean distance](https://en.wikipedia.org/wiki/Euclidean_distance)).
**Syntax**
```sql
L2Normalize(tuple)
```
Alias: `normalizeL1`.
**Arguments**
- `tuple` — [Tuple](../../sql-reference/data-types/tuple.md).
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**Returned value**
- Unit vector.
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Type: [Tuple](../../sql-reference/data-types/tuple.md) of [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT L2Normalize((3, 4));
```
Result:
```text
┌─L2Normalize((3, 4))─┐
│ (0.6,0.8) │
└─────────────────────┘
```
## LinfNormalize
Calculates the unit vector of a given vector (the values of the tuple are the coordinates) in `L_{inf}` space (using [maximum norm](https://en.wikipedia.org/wiki/Norm_(mathematics)#Maximum_norm_(special_case_of:_infinity_norm,_uniform_norm,_or_supremum_norm))).
**Syntax**
```sql
LinfNormalize(tuple)
```
Alias: `normalizeLinf `.
**Arguments**
- `tuple` — [Tuple](../../sql-reference/data-types/tuple.md).
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**Returned value**
- Unit vector.
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Type: [Tuple](../../sql-reference/data-types/tuple.md) of [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT LinfNormalize((3, 4));
```
Result:
```text
┌─LinfNormalize((3, 4))─┐
│ (0.75,1) │
└───────────────────────┘
```
## LpNormalize
Calculates the unit vector of a given vector (the values of the tuple are the coordinates) in `Lp` space (using [p-norm](https://en.wikipedia.org/wiki/Norm_(mathematics)#p-norm)).
**Syntax**
```sql
LpNormalize(tuple, p)
```
Alias: `normalizeLp `.
**Arguments**
- `tuple` — [Tuple](../../sql-reference/data-types/tuple.md).
- `p` — The power. Possible values: any number from [1;inf). [UInt](../../sql-reference/data-types/int-uint.md) or [Float](../../sql-reference/data-types/float.md).
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**Returned value**
- Unit vector.
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Type: [Tuple](../../sql-reference/data-types/tuple.md) of [Float](../../sql-reference/data-types/float.md).
**Example**
Query:
```sql
SELECT LpNormalize((3, 4),5);
```
Result:
```text
┌─LpNormalize((3, 4), 5)──────────────────┐
│ (0.7187302630182624,0.9583070173576831) │
└─────────────────────────────────────────┘
```
## cosineDistance
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Calculates the cosine distance between two vectors (the values of the tuples are the coordinates). The smaller the returned value is, the more similar are the vectors.
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**Syntax**
```sql
cosineDistance(vector1, vector2)
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```
**Arguments**
- `vector1` — First tuple. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
- `vector2` — Second tuple. [Tuple](../../sql-reference/data-types/tuple.md) or [Array](../../sql-reference/data-types/array.md).
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**Returned value**
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- Cosine of the angle between two vectors subtracted from one.
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Type: [Float](../../sql-reference/data-types/float.md).
**Examples**
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Query:
```sql
SELECT cosineDistance((1, 2), (2, 3));
```
Result:
```text
┌─cosineDistance((1, 2), (2, 3))─┐
│ 0.007722123286332261 │
└────────────────────────────────┘
```