8.6. Mathematical Functions and Operators

Mathematical Operators

Mathematical Functions

abs(x) → [same as input]

Returns the absolute value of x.

cbrt(x) → double

Returns the cube root of x.

ceil(x) → [same as input]

This is an alias for ceiling().

ceiling(x) → [same as input]

Returns x rounded up to the nearest integer.

cosine_similarity(x, y) → double

Returns the cosine similarity between the sparse vectors x and y:

SELECT cosine_similarity(MAP(ARRAY['a'], ARRAY[1.0]), MAP(ARRAY['a'], ARRAY[2.0])); -- 1.0

degrees(x) → double

Converts angle x in radians to degrees.

e() → double

Returns the constant Euler’s number.

exp(x) → double

Returns Euler’s number raised to the power of x.

floor(x) → [same as input]

Returns x rounded down to the nearest integer.

from_base(string, radix) → bigint

Returns the value of string interpreted as a base-radix number.

inverse_normal_cdf(mean, sd, p) → double

Compute the inverse of the Normal cdf with given mean and standard deviation (sd) for the cumulative probability (p): P(N < n). The mean must be a real value and the standard deviation must be a real and positive value. The probability p must lie on the interval (0, 1).

normal_cdf(mean, sd, v) → double

Compute the Normal cdf with given mean and standard deviation (sd): P(N < v; mean, sd). The mean and value v must be real values and the standard deviation must be a real and positive value.

inverse_beta_cdf(a, b, p) → double

Compute the inverse of the Beta cdf with given a, b parameters for the cumulative probability (p): P(N < n). The a, b parameters must be positive real values. The probability p must lie on the interval [0, 1].

beta_cdf(a, b, v) → double

Compute the Beta cdf with given a, b parameters: P(N < v; a, b). The a, b parameters must be positive real numbers and value v must be a real value. The value v must lie on the interval [0, 1].

ln(x) → double

Returns the natural logarithm of x.

log2(x) → double

Returns the base 2 logarithm of x.

log10(x) → double

Returns the base 10 logarithm of x.

mod(n, m) → [same as input]

Returns the modulus (remainder) of n divided by m.

pi() → double

Returns the constant Pi.

pow(x, p) → double

This is an alias for power().

power(x, p) → double

Returns x raised to the power of p.

radians(x) → double

Converts angle x in degrees to radians.

rand() → double

This is an alias for random().

random() → double

Returns a pseudo-random value in the range 0.0 <= x < 1.0.

random(n) → [same as input]

Returns a pseudo-random number between 0 and n (exclusive).

round(x) → [same as input]

Returns x rounded to the nearest integer.

round(x, d) → [same as input]

Returns x rounded to d decimal places.

sign(x) → [same as input]

Returns the signum function of x, that is:

• 0 if the argument is 0,
• 1 if the argument is greater than 0,
• -1 if the argument is less than 0.

For double arguments, the function additionally returns:

• NaN if the argument is NaN,
• 1 if the argument is +Infinity,
• -1 if the argument is -Infinity.

sqrt(x) → double

Returns the square root of x.

to_base(x, radix) → varchar

Returns the base-radix representation of x.

truncate(x) → double

Returns x rounded to integer by dropping digits after decimal point.

truncate(x, n) → double

Returns x truncated to n decimal places. n can be negative to truncate n digits left of the decimal point.

Example: truncate(REAL '12.333', -1) -> result is 10.0 truncate(REAL '12.333', 0) -> result is 12.0 truncate(REAL '12.333', 1) -> result is 12.3

width_bucket(x, bound1, bound2, n) → bigint

Returns the bin number of x in an equi-width histogram with the specified bound1 and bound2 bounds and n number of buckets.

width_bucket(x, bins) → bigint

Returns the bin number of x according to the bins specified by the array bins. The bins parameter must be an array of doubles and is assumed to be in sorted ascending order.

Statistical Functions

wilson_interval_lower(successes, trials, z) → double

Returns the lower bound of the Wilson score interval of a Bernoulli trial process at a confidence specified by the z-score z.

wilson_interval_upper(successes, trials, z) → double

Returns the upper bound of the Wilson score interval of a Bernoulli trial process at a confidence specified by the z-score z.

Trigonometric Functions

All trigonometric function arguments are expressed in radians. See unit conversion functions degrees() and radians().

acos(x) → double

Returns the arc cosine of x.

asin(x) → double

Returns the arc sine of x.

atan(x) → double

Returns the arc tangent of x.

atan2(y, x) → double

Returns the arc tangent of y / x.

cos(x) → double

Returns the cosine of x.

cosh(x) → double

Returns the hyperbolic cosine of x.

sin(x) → double

Returns the sine of x.

tan(x) → double

Returns the tangent of x.

tanh(x) → double

Returns the hyperbolic tangent of x.

Floating Point Functions

infinity() → double

Returns the constant representing positive infinity.

is_finite(x) → boolean

Determine if x is finite.

is_infinite(x) → boolean

Determine if x is infinite.

is_nan(x) → boolean

Determine if x is not-a-number.

nan() → double

Returns the constant representing not-a-number.