sumKahan

Introduced in: v1.1.0

Calculates the sum of the numbers with Kahan compensated summation algorithm. Slower than sum function. The compensation works only for Float types. For the Decimal and Interval types, which are backed by integers, the exact summation of sum is used instead.

Syntax

sumKahan(x)

Arguments

• x — Input value. Integer or Float or Decimal or Interval

Returned value

Returns the sum of numbers. (U)Int* or Float* or Decimal or Interval

Examples

Demonstrating precision improvement with Kahan summation

SELECT sum(0.1), sumKahan(0.1) FROM numbers(10);

┌───────────sum(0.1)─┬─sumKahan(0.1)─┐
│ 0.9999999999999999 │             1 │
└────────────────────┴───────────────┘