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 x) | absolute value | abs(-17.4) | 17.4 |
| cbrt(dp) | dp | cube root | cbrt(27.0) | 3.0 |
| ceil(numeric) | numeric | smallest integer not less than argument | ceil(-42.8) | -42 |
| degrees(dp) | dp | radians to degrees | degrees(0.5) | 28.6478897565412 |
| exp(dp) | dp | exponential | exp(1.0) | 2.71828182845905 |
| floor(numeric) | numeric | largest integer not greater than argument | floor(-42.8) | -43 |
| ln(dp) | dp | natural logarithm | ln(2.0) | 0.693147180559945 |
| log(dp) | dp | base 10 logarithm | log(100.0) | 2.0 |
| log(b numeric, x numeric) | numeric | logarithm to base b | log(2.0, 64.0) | 6.0 |
| mod(y, x) | (same as argument types) | remainder of y/x | mod(9,4) | 1 |
| pi() | dp | "Pi" constant | pi() | 3.14159265358979 |
| pow(e dp, n dp) | dp | raise a number to exponent e | pow(9.0, 3.0) | 729.0 |
| radians(dp) | dp | degrees to radians | radians(45.0) | 0.785398163397448 |
| random() | dp | value between 0.0 to 1.0 | random() | |
| round(dp) | dp | round to nearest integer | round(42.4) | 42 |
| round(v numeric, s integer) | numeric | round to s decimal places | round(42.4382, 2) | 42.44 |
| sqrt(dp) | dp | square root | sqrt(2.0) | 1.4142135623731 |
| trunc(dp) | dp | truncate toward zero | trunc(42.8) | 42 |
| trunc(numeric, s integer) | numeric | truncate to s decimal places | round(42.4382, 2) | 42.43 |
In the table above, "dp" indicates double precision. 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. Functions returning a numeric result take numeric input arguments, unless otherwise specified. 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.