LOG()

All functions > MATH > LOG()

Returns the logarithm of a number to a specified base.

Signatures

Logarithm

Returns: Logarithm of number to base base

LOG(base: B, number: T) → DOUBLE

With:

• B : Integer or floating-point
• T : Floating-point type (FLOAT, DOUBLE)

Signature notes:

• The base may be an integer (e.g. LOG(2, x), LOG(10, x)) or a floating-point number
• The number argument must be floating-point; cast integers explicitly if needed
• Both base and number must be positive, and the base must not be 1
• LOG(base, 1.0) = 0 for any valid base
• Returns NULL if any input is NULL

Examples

SELECT
    f1 := LOG(10, 100E0), -- Log base 10 with integer base
    f2 := LOG(10, 1000E0), -- Another log base 10
    f3 := LOG(2, 8E0), -- Log base 2
    f4 := LOG(2, 16E0), -- Log base 2 of 16
    f5 := LOG(10E0, 100E0), -- Floating-point base also accepted
    f6 := LOG(10, 1E0) -- Log of 1 is always 0
;