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8.3. Mathematical Functions and Operators

Mathematical operators are provided for many EnterpriseDB types. For types without common mathematical conventions for all possible permutations (e.g., date/time types) we describe the actual behavior in subsequent sections.

Table 8-2 shows the available mathematical operators.

Table 8-2. Mathematical Operators

OperatorDescriptionExampleResult
+ addition2 + 35
- subtraction2 - 3-1
* multiplication2 * 36
/ division (integer division truncates results)4 / 22
% modulo (remainder)5 % 41
^ exponentiation2.0 ^ 3.08
|/ square root|/ 25.05
||/ cube root||/ 27.03
! factorial5 !120
!! factorial (prefix operator)!! 5120
@ absolute value@ -5.05
& bitwise AND91 & 1511
| bitwise OR32 | 335
# bitwise XOR17 # 520
~ bitwise NOT~1-2
<< bitwise shift left1 << 416
>> bitwise shift right8 >> 22

The bitwise operators work only on integral data types, whereas the others are available for all numeric data types.

Table 8-3 shows the available mathematical functions. Many of these functions are provided in multiple forms with different argument types. Except where noted, any given form of a function returns the same data type as its argument. The functions working with DOUBLE PRECISION data are mostly implemented on top of the host system's C library; accuracy and behavior in boundary cases may therefore vary depending on the host system.

Table 8-3. Mathematical Functions

FunctionReturn TypeDescriptionExampleResult
abs(x)(same as x)absolute valueabs(-17.4)17.4
cbrt(DOUBLE PRECISION)DOUBLE PRECISIONcube rootcbrt(27.0)3
ceil(DOUBLE PRECISION or NUMERIC)(same as input)smallest integer not less than argumentceil(-42.8)-42
ceiling(DOUBLE PRECISION or NUMERIC)(same as input)smallest integer not less than argument (alias for ceil)ceiling(-95.3)-95
degrees(DOUBLE PRECISION)DOUBLE PRECISIONradians to degreesdegrees(0.5)28.6478897565412
exp(DOUBLE PRECISION or NUMERIC)(same as input)exponentialexp(1.0)2.71828182845905
floor(DOUBLE PRECISION or NUMERIC)(same as input)largest integer not greater than argumentfloor(-42.8)-43
ln(DOUBLE PRECISION or NUMERIC)(same as input)natural logarithmln(2.0)0.693147180559945
log(DOUBLE PRECISION or NUMERIC)(same as input)base 10 logarithmlog(100.0)2
log(b NUMERIC, x NUMERIC)NUMERIClogarithm to base blog(2.0, 64.0)6.0000000000
nvl(x, y)(same as argument types; where both arguments are of the same datatype)if x is null, then nvl returnsynvl(9,0)9
mod(y, x)(same as argument types)remainder of y/xmod(9,4)1
pi()DOUBLE PRECISION"π" constantpi()3.14159265358979
power(a DOUBLE PRECISION, b DOUBLE PRECISION)DOUBLE PRECISIONa raised to the power of bpower(9.0, 3.0)729
power(a NUMERIC, b NUMERIC)NUMERICa raised to the power of bpower(9.0, 3.0)729
radians(DOUBLE PRECISION)DOUBLE PRECISIONdegrees to radiansradians(45.0)0.785398163397448
random()DOUBLE PRECISIONrandom value between 0.0 and 1.0random() 
round(DOUBLE PRECISION or NUMERIC)(same as input)round to nearest integerround(42.4)42
round(v NUMERIC, s INTEGER)NUMERICround to s decimal placesround(42.4382, 2)42.44
setseed(DOUBLE PRECISION)INTEGERset seed for subsequent random() callssetseed(0.54823)1177314959
sign(DOUBLE PRECISION or NUMERIC)(same as input)sign of the argument (-1, 0, +1)sign(-8.4)-1
sqrt(DOUBLE PRECISION or NUMERIC)(same as input)square rootsqrt(2.0)1.4142135623731
trunc(DOUBLE PRECISION or NUMERIC)(same as input)truncate toward zerotrunc(42.8)42
trunc(v NUMERIC, s INTEGER)NUMERICtruncate to s decimal placestrunc(42.4382, 2)42.43
width_bucket(op NUMERIC, b1 NUMERIC, b2 NUMERIC, count INTEGER)INTEGERreturn the bucket to which operand would be assigned in an equidepth histogram with count buckets, an upper bound of b1, and a lower bound of b2width_bucket(5.35, 0.024, 10.06, 5)3

Finally, Table 8-4 shows the available trigonometric functions. All trigonometric functions take arguments and return values of type double precision.

Table 8-4. Trigonometric Functions

FunctionDescription
acos(x)inverse cosine
asin(x)inverse sine
atan(x)inverse tangent
atan2(x, y)inverse tangent of x/y
cos(x)cosine
cot(x)cotangent
sin(x)sine
tan(x)tangent
 
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