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Built-in math functions

This topic describes the built-in math functions supported by Nebula Graph.

Note

If the argument is NULL, the output is undefined.

abs()

abs() returns the absolute value of the argument.

Syntax: abs(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN abs(-10);
+------------+
| abs(-(10)) |
+------------+
| 10         |
+------------+
nebula> RETURN abs(5-6);
+------------+
| abs((5-6)) |
+------------+
| 1          |
+------------+

floor()

floor() returns the largest integer value smaller than or equal to the argument.(Rounds down)

Syntax: floor(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN floor(9.9);
+------------+
| floor(9.9) |
+------------+
| 9.0        |
+------------+

ceil()

ceil() returns the smallest integer greater than or equal to the argument.(Rounds up)

Syntax: ceil(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN ceil(9.1);
+-----------+
| ceil(9.1) |
+-----------+
| 10.0      |
+-----------+

round()

round() returns the rounded value of the specified number. Pay attention to the floating-point precision when using this function.

Syntax: round(<expression>, <digit>)

  • expression: An expression of which the result type is double.
  • digit: Decimal digits. If digit is less than 0, round at the left of the decimal point.
  • Result type: Double

Example:

nebula> RETURN round(314.15926, 2);
+--------------------+
| round(314.15926,2) |
+--------------------+
| 314.16             |
+--------------------+
nebula> RETURN round(314.15926, -1);
+-----------------------+
| round(314.15926,-(1)) |
+-----------------------+
| 310.0                 |
+-----------------------+

sqrt()

sqrt() returns the square root of the argument.

Syntax: sqrt(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN sqrt(9);
+---------+
| sqrt(9) |
+---------+
| 3.0     |
+---------+

cbrt()

cbrt() returns the cubic root of the argument.

Syntax: cbrt(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN cbrt(8);
+---------+
| cbrt(8) |
+---------+
| 2.0     |
+---------+

hypot()

hypot() returns the hypotenuse of a right-angled triangle.

Syntax: hypot(<expression_x>,<expression_y>)

  • expression_x, expression_y: An expression of which the result type is double. They represent the side lengths x and y of a right triangle.
  • Result type: Double

Example:

nebula> RETURN hypot(3,2*2);
+----------------+
| hypot(3,(2*2)) |
+----------------+
| 5.0            |
+----------------+

pow()

pow() returns the result of xy.

Syntax: pow(<expression_x>,<expression_y>,)

  • expression_x: An expression of which the result type is double. It represents the base x.
  • expression_y: An expression of which the result type is double. It represents the exponential y.
  • Result type: Double

Example:

nebula> RETURN pow(3,3);
+----------+
| pow(3,3) |
+----------+
| 27       |
+----------+

exp()

exp() returns the result of ex.

Syntax: exp(<expression>)

  • expression: An expression of which the result type is double. It represents the exponential x.
  • Result type: Double

Example:

nebula> RETURN exp(2);
+------------------+
| exp(2)           |
+------------------+
| 7.38905609893065 |
+------------------+

exp2()

exp2() returns the result of 2x.

Syntax: exp2(<expression>)

  • expression: An expression of which the result type is double. It represents the exponential x.
  • Result type: Double

Example:

nebula> RETURN exp2(3);
+---------+
| exp2(3) |
+---------+
| 8.0     |
+---------+

log()

log() returns the base-e logarithm of the argument. (\(log_{e}{N}\))

Syntax: log(<expression>)

  • expression: An expression of which the result type is double. It represents the antilogarithm N.
  • Result type: Double

Example:

nebula> RETURN log(8);
+--------------------+
| log(8)             |
+--------------------+
| 2.0794415416798357 |
+--------------------+

log2()

log2() returns the base-2 logarithm of the argument. (\(log_{2}{N}\))

Syntax: log2(<expression>)

  • expression: An expression of which the result type is double. It represents the antilogarithm N.
  • Result type: Double

Example:

nebula> RETURN log2(8);
+---------+
| log2(8) |
+---------+
| 3.0     |
+---------+

log10()

log10() returns the base-10 logarithm of the argument. (\(log_{10}{N}\))

Syntax: log10(<expression>)

  • expression: An expression of which the result type is double. It represents the antilogarithm N.
  • Result type: Double

Example:

nebula> RETURN log10(100);
+------------+
| log10(100) |
+------------+
| 2.0        |
+------------+

sin()

sin() returns the sine of the argument. Users can convert angles to radians using the function radians().

Syntax: sin(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN sin(3);
+--------------------+
| sin(3)             |
+--------------------+
| 0.1411200080598672 |
+--------------------+

asin()

asin() returns the inverse sine of the argument. Users can convert angles to radians using the function radians().

Syntax: asin(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN asin(0.5);
+--------------------+
| asin(0.5)          |
+--------------------+
| 0.5235987755982989 |
+--------------------+

cos()

cos() returns the cosine of the argument. Users can convert angles to radians using the function radians().

Syntax: cos(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN cos(0.5);
+--------------------+
| cos(0.5)           |
+--------------------+
| 0.8775825618903728 |
+--------------------+

acos()

acos() returns the inverse cosine of the argument. Users can convert angles to radians using the function radians().

Syntax: acos(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN acos(0.5);
+--------------------+
| acos(0.5)          |
+--------------------+
| 1.0471975511965979 |
+--------------------+

tan()

tan() returns the tangent of the argument. Users can convert angles to radians using the function radians().

Syntax: tan(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN tan(0.5);
+--------------------+
| tan(0.5)           |
+--------------------+
| 0.5463024898437905 |
+--------------------+

atan()

atan() returns the inverse tangent of the argument. Users can convert angles to radians using the function radians().

Syntax: atan(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Double

Example:

nebula> RETURN atan(0.5);
+--------------------+
| atan(0.5)          |
+--------------------+
| 0.4636476090008061 |
+--------------------+

rand()

rand() returns a random floating point number in the range from 0 (inclusive) to 1 (exclusive); i.e.[0,1).

Syntax: rand()

  • Result type: Double

Example:

nebula> RETURN rand();
+--------------------+
| rand()             |
+--------------------+
| 0.6545837172298736 |
+--------------------+

rand32()

rand32() returns a random 32-bit integer in [min, max).

Syntax: rand32(<expression_min>,<expression_max>)

  • expression_min: An expression of which the result type is int. It represents the minimum min.
  • expression_max: An expression of which the result type is int. It represents the maximum max.
  • Result type: Int
  • If you set only one argument, it is parsed as max and min is 0 by default. If you set no argument, the system returns a random signed 32-bit integer.

Example:

nebula> RETURN rand32(1,100);
+---------------+
| rand32(1,100) |
+---------------+
| 63            |
+---------------+

rand64()

rand64() returns a random 64-bit integer in [min, max).

Syntax: rand64(<expression_min>,<expression_max>)

  • expression_min: An expression of which the result type is int. It represents the minimum min.
  • expression_max: An expression of which the result type is int. It represents the maximum max.
  • Result type: Int
  • If you set only one argument, it is parsed as max and min is 0 by default. If you set no argument, the system returns a random signed 64-bit integer.

Example:

nebula> RETURN rand64(1,100);
+---------------+
| rand64(1,100) |
+---------------+
| 34            |
+---------------+

std()

std() returns the population standard deviation.

Syntax: std(<expression>)

  • Result type: Double

Example:

nebula> MATCH (v:player) RETURN std(v.player.age);
+-------------------+
| std(v.player.age) |
+-------------------+
| 6.423895701687502 |
+-------------------+

sum()

sum() returns the sum value.

Syntax: sum(<expression>)

  • Result type: Same as the original argument.

Example:

nebula> MATCH (v:player) RETURN sum(v.player.age);
+-------------------+
| sum(v.player.age) |
+-------------------+
| 1698              |
+-------------------+

bit_and()

bit_and() returns the result of bitwise AND.

Syntax: bit_and(<expression_1>,<expression_2>)

  • expression_1, expression_2: An expression of which the result type is int.
  • Result type: Int

Example:

nebula> RETURN bit_and(5,6);
+--------------+
| bit_and(5,6) |
+--------------+
| 4            |
+--------------+

bit_or()

bit_or() returns the result of bitwise OR.

Syntax: bit_or(<expression_1>,<expression_2>)

  • expression_1, expression_2: An expression of which the result type is int.
  • Result type: Int

Example:

nebula> RETURN bit_or(5,6);
+-------------+
| bit_or(5,6) |
+-------------+
| 7           |
+-------------+

bit_xor()

bit_xor() returns the result of bitwise XOR.

Syntax: bit_xor(<expression_1>,<expression_2>)

  • expression_1, expression_2: An expression of which the result type is int.
  • Result type: Int

Example:

nebula> RETURN bit_xor(5,6);
+--------------+
| bit_xor(5,6) |
+--------------+
| 3            |
+--------------+

size()

size() returns the number of elements in a list or a map.

Syntax: size(<expression>)

  • expression: An expression for a list or map.
  • Result type: Int

Example:

nebula> RETURN size([1,2,3,4]);
+-----------------+
| size([1,2,3,4]) |
+-----------------+
| 4               |
+-----------------+

range()

range() returns a list of integers from [start,end] in the specified steps.

Syntax: range(<expression_start>,<expression_end>[,<expression_step>])

  • expression_start: An expression of which the result type is int. It represents the starting value start.
  • expression_end: An expression of which the result type is int. It represents the end value end.
  • expression_step: An expression of which the result type is int. It represents the step size step, step is 1 by default.
  • Result type: List

Example:

nebula> RETURN range(1,3*3,2);
+------------------+
| range(1,(3*3),2) |
+------------------+
| [1, 3, 5, 7, 9]  |
+------------------+

sign()

sign() returns the signum of the given number. If the number is 0, the system returns 0. If the number is negative, the system returns -1. If the number is positive, the system returns 1.

Syntax: sign(<expression>)

  • expression: An expression of which the result type is double.
  • Result type: Int

Example:

nebula> RETURN sign(10);
+----------+
| sign(10) |
+----------+
| 1        |
+----------+

e()

e() returns the base of the natural logarithm, e (2.718281828459045).

Syntax: e()

  • Result type: Double

Example:

nebula> RETURN e();
+-------------------+
| e()               |
+-------------------+
| 2.718281828459045 |
+-------------------+

pi()

pi() returns the mathematical constant pi (3.141592653589793).

Syntax: pi()

  • Result type: Double

Example:

nebula> RETURN pi();
+-------------------+
| pi()              |
+-------------------+
| 3.141592653589793 |
+-------------------+

radians()

radians() converts angles to radians.

Syntax: radians(<angle>)

  • Result type: Double

Example:

nebula> RETURN radians(180);
+-------------------+
| radians(180)      |
+-------------------+
| 3.141592653589793 |
+-------------------+

Last update: August 12, 2022