quantiles Functions
quantiles
Syntax: quantiles(level1, level2, …)(x)
All the quantile functions also have corresponding quantiles functions: quantiles
, quantilesDeterministic
, quantilesTiming
, quantilesTimingWeighted
, quantilesExact
, quantilesExactWeighted
, quantileInterpolatedWeighted
, quantilesTDigest
, quantilesBFloat16
. These functions calculate all the quantiles of the listed levels in one pass, and return an array of the resulting values.
quantilesExactExclusive
Exactly computes the quantiles of a numeric data sequence.
To get exact value, all the passed values are combined into an array, which is then partially sorted. Therefore, the function consumes O(n)
memory, where n
is a number of values that were passed. However, for a small number of values, the function is very effective.
This function is equivalent to PERCENTILE.EXC Excel function, (type R6).
Works more efficiently with sets of levels than quantileExactExclusive.
Syntax
quantilesExactExclusive(level1, level2, ...)(expr)
Arguments
expr
— Expression over the column values resulting in numeric data types, Date or DateTime.
Parameters
level
— Levels of quantiles. Possible values: (0, 1) — bounds not included. Float.
Returned value
- Array of quantiles of the specified levels.
Type of array values:
- Float64 for numeric data type input.
- Date if input values have the
Date
type. - DateTime if input values have the
DateTime
type.
Example
Query:
CREATE TABLE num AS numbers(1000);
SELECT quantilesExactExclusive(0.25, 0.5, 0.75, 0.9, 0.95, 0.99, 0.999)(x) FROM (SELECT number AS x FROM num);
Result:
┌─quantilesExactExclusive(0.25, 0.5, 0.75, 0.9, 0.95, 0.99, 0.999)(x)─┐
│ [249.25,499.5,749.75,899.9,949.9499999999999,989.99,998.999] │
└─────────────────────────────────────────────────────────────────────┘
quantilesExactInclusive
Exactly computes the quantiles of a numeric data sequence.
To get exact value, all the passed values are combined into an array, which is then partially sorted. Therefore, the function consumes O(n)
memory, where n
is a number of values that were passed. However, for a small number of values, the function is very effective.
This function is equivalent to PERCENTILE.INC Excel function, (type R7).
Works more efficiently with sets of levels than quantileExactInclusive.
Syntax
quantilesExactInclusive(level1, level2, ...)(expr)
Arguments
expr
— Expression over the column values resulting in numeric data types, Date or DateTime.
Parameters
level
— Levels of quantiles. Possible values: [0, 1] — bounds included. Float.
Returned value
- Array of quantiles of the specified levels.
Type of array values:
- Float64 for numeric data type input.
- Date if input values have the
Date
type. - DateTime if input values have the
DateTime
type.
Example
Query:
CREATE TABLE num AS numbers(1000);
SELECT quantilesExactInclusive(0.25, 0.5, 0.75, 0.9, 0.95, 0.99, 0.999)(x) FROM (SELECT number AS x FROM num);
Result:
┌─quantilesExactInclusive(0.25, 0.5, 0.75, 0.9, 0.95, 0.99, 0.999)(x)─┐
│ [249.75,499.5,749.25,899.1,949.05,989.01,998.001] │
└─────────────────────────────────────────────────────────────────────┘
quantilesGK
quantilesGK
works similarly with quantileGK
but allows us to calculate quantities at different levels simultaneously and returns an array.
Syntax
quantilesGK(accuracy, level1, level2, ...)(expr)
Returned value
- Array of quantiles of the specified levels.
Type of array values:
- Float64 for numeric data type input.
- Date if input values have the
Date
type. - DateTime if input values have the
DateTime
type.
Example
Query:
SELECT quantilesGK(1, 0.25, 0.5, 0.75)(number + 1)
FROM numbers(1000)
┌─quantilesGK(1, 0.25, 0.5, 0.75)(plus(number, 1))─┐
│ [1,1,1] │
└──────────────────────────────────────────────────┘
SELECT quantilesGK(10, 0.25, 0.5, 0.75)(number + 1)
FROM numbers(1000)
┌─quantilesGK(10, 0.25, 0.5, 0.75)(plus(number, 1))─┐
│ [156,413,659] │
└───────────────────────────────────────────────────┘
SELECT quantilesGK(100, 0.25, 0.5, 0.75)(number + 1)
FROM numbers(1000)
┌─quantilesGK(100, 0.25, 0.5, 0.75)(plus(number, 1))─┐
│ [251,498,741] │
└────────────────────────────────────────────────────┘
SELECT quantilesGK(1000, 0.25, 0.5, 0.75)(number + 1)
FROM numbers(1000)
┌─quantilesGK(1000, 0.25, 0.5, 0.75)(plus(number, 1))─┐
│ [249,499,749] │
└─────────────────────────────────────────────────────┘