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wiki:smartaltitude_webgis_calc_operators_functions

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List of mathematical operators and functions which can be used in the Smart Altitude WebGIS calculation tool.

Note: remember to always put a space character between operators and operands. While some operators work without extra space characters, others might not.

Mathematical Operators

OperatorDescriptionExampleValue
+addition2 + 35
-subtraction2 - 3-1
*multiplication2 * 36
/division (integer division - truncates the result) - 0 as argument not allowed5 / 22
%modulo (remainder of division) - 0 as argument not allowed5 % 21
/\exponentiation (associates left to right)2 /\ 38
I/square root - negative argument not allowed/ 255
II/cube root - negative argument not allowed/ 273
@absolute value@ -2.422.42

Mathematical Functions

FunctionDescriptionExampleResult
abs(x)absolute value, same as operator @abs(-2.42)2.42
cbrt(x)cube rootcbrt(27.0)3
ceil(x)nearest integer greater than or equal to argumentceil(-42.8)-42
degrees(x)radians to degreesdegrees(0.5)28.64…
div(y, x)integer quotient of y/xdiv(9, 4)2
exp(x)exponentialexp(1.0)2.718…
floor(x)nearest integer less than or equal to argumentfloor(-42.8)-43
ln(x)natural logarithm - 0 as argument not allowedln(2.0)0.693…
log(x)base 10 logarithm - 0 as argument not allowedlog(100.0)2
log(b, x)logarithm to base blog(2.0, 64.0)6
mod(x, y)remainder of y/xmod(9, 4)1
pi()pi constantpi()3.141…
power(x, y)x raised to the power of ypower(9, 2)729
radians(x)degrees to radiansradians(45.0)0.785…
round(x)round to nearest integerround(42.4)42
round(x, y)round to y decimal placesround(32.36, 1)32.4
sign(x)sign of the argument (-1, 0, +1)sign(-4.1)-1
sqrt(x)square root, same as operator I\ - negative argument not allowedsqrt(2.0)1.414…
trunc(x)truncate toward zerotrunc(42.8)42
trunc(x, y)truncate to y decimal placestrunc(42.43, 1)42.4

Raster Functions

FunctionDescription
min()minimum pixel value per LAU unit
max()maximum pixel value per LAU unit
count()number of pixels per LAU unit
sum()sum of pixel values per LAU unit
avg()average for pixel values per LAU unit
med()median for pixel values per LAU unit

Random Functions

FunctionDescription
random()random value in the range 0.0 ⇐ x < 1.0


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