Table 4-2. Mathematical Operators
Name | Description | Example | Result |
---|---|---|---|
+ | Addition | 2 + 3 | 5 |
- | Subtraction | 2 - 3 | -1 |
* | Multiplication | 2 * 3 | 6 |
/ | Division (integer division truncates results) | 4 / 2 | 2 |
% | Modulo (remainder) | 5 % 4 | 1 |
^ | Exponentiation | 2.0 ^ 3.0 | 8.0 |
|/ | Square root | |/ 25.0 | 5.0 |
||/ | Cube root | ||/ 27.0 | 3 |
! | Factorial | 5 ! | 120 |
!! | Factorial (prefix operator) | !! 5 | 120 |
@ | Absolute value | @ -5.0 | 5.0 |
& | Binary AND | 91 & 15 | 11 |
| | Binary OR | 32 | 3 | 35 |
# | Binary XOR | 17 # 5 | 20 |
~ | Binary NOT | ~1 | -2 |
<< | Binary shift left | 1 << 4 | 16 |
>> | Binary shift right | 8 >> 2 | 2 |
The "binary" operators are also available for the bit string types BIT and BIT VARYING.
Table 4-3. Bit String Binary Operators
Example | Result |
---|---|
B'10001' & B'01101' | 00001 |
B'10001' | B'01101' | 11101 |
B'10001' # B'01101' | 11110 |
~ B'10001' | 01110 |
B'10001' << 3 | 01000 |
B'10001' >> 2 | 00100 |
Table 4-4. Mathematical Functions
Function | Return Type | Description | Example | Result |
---|---|---|---|---|
abs(x) | (same as argument type) | absolute value | abs(-17.4) | 17.4 |
cbrt(double precision) | double precision | cube root | cbrt(27.0) | 3.0 |
ceil(numeric) | numeric | smallest integer not less than argument | ceil(-42.8) | -42 |
degrees(double precision) | double precision | convert radians to degrees | degrees(0.5) | 28.6478897565412 |
exp(double precision) | double precision | exponential function | exp(1.0) | 2.71828182845905 |
floor(numeric) | numeric | largest integer not greater than argument | floor(-42.8) | -43 |
ln(double precision) | double precision | natural logarithm | ln(2.0) | 0.693147180559945 |
log(double precision) | double precision | base 10 logarithm | log(100.0) | 2.0 |
log(base numeric, x numeric) | numeric | logarithm to specified base | log(2.0, 64.0) | 6.0 |
mod(y, x) | (same as argument types) | remainder (modulo) of the division y/x | mod(9,4) | 1 |
pi() | double precision | "Pi" constant | pi() | 3.14159265358979 |
pow(double precision, double precision) | double precision | raise a number to the specified exponent | pow(9.0, 3.0) | 729.0 |
radians(double precision) | double precision | convert degrees to radians | radians(45.0) | 0.785398163397448 |
random() | double precision | a pseudo-random value between 0.0 to 1.0 | random() | |
round(double precision) | double precision | round to nearest integer | round(42.4) | 42 |
round(value numeric, scale integer) | numeric | round to specified number of decimal places | round(42.4382, 2) | 42.44 |
sqrt(double precision) | double precision | square root | sqrt(2.0) | 1.4142135623731 |
trunc(double precision) | double precision | truncate (toward zero) | trunc(42.8) | 42 |
trunc(value numeric, scale integer) | numeric | truncate to specified number of decimal places | round(42.4382, 2) | 42.43 |
The functions exp, ln, log, pow, round (1 argument), sqrt, and trunc (1 argument) are also available for the type numeric in place of double precision. Many of these functions are implemented on top of the host system's C library and behavior in boundary cases could therefore vary depending on the operating system.
Table 4-5. Trigonometric Functions
Function | Description |
---|---|
acos(x) | inverse cosine |
asin(x) | inverse sine |
atan(x) | inverse tangent |
atan2(x, y) | inverse tangent of y/x |
cos(x) | cosine |
cot(x) | cotangent |
sin(x) | sine |
tan(x) | tangent |
All trigonometric functions have arguments and return values of type double precision.