quantileBFloat16Weighted

Like quantileBFloat16 but takes into account the weight of each sequence member.

Computes an approximate quantile of a sample consisting of bfloat16 numbers. bfloat16 is a floating-point data type with 1 sign bit, 8 exponent bits and 7 fraction bits. The function converts input values to 32-bit floats and takes the most significant 16 bits. Then it calculates bfloat16 quantile value and converts the result to a 64-bit float by appending zero bits. The function is a fast quantile estimator with a relative error no more than 0.390625%.

Syntax

Alias: medianBFloat16

Arguments

expr — Column with numeric data. Integer, Float.

Parameters

level — Level of quantile. Optional. Possible values are in the range from 0 to 1. Default value: 0.5. Float.

Returned value

Approximate quantile of the specified level.

Type: Float64.

Example

Input table has an integer and a float columns:

Query to calculate 0.75-quantile (third quartile):

Result:

Note that all floating point values in the example are truncated to 1.0 when converting to bfloat16.

See Also