8.6. Mathematical Functions and Operators
Mathematical Operators
Operator | Description |
---|---|
+ | Addition |
- | Subtraction |
* | Multiplication |
/ | Division (integer division performs truncation) |
% | Modulus (remainder) |
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.
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.