Question

Which formulas are supported when performing custom calculations?

Answer

Examples

FormulaDescription
Heading - COGDifference between Heading and COG
DELTAPERSEC(MAKEABSOLUTEANGLECONTINUOUS(Heading))Rate of turn in degrees per second
DELTAPERSEC(BoatSpeed) * 60Acceleration in knots per minute
BoatSpeed / -(FILTER(DELTASEC(BoatSpeed, 10), DELTASEC(BoatSpeed, 10) < 0) / 10)When decelerating, how many seconds to zero knots at current 10 second deceleration average

Infix Operators

OperatorDescriptionNotes
+Addition
-Subtraction
*Multiplication
/Division
<Less thanTo be used with FILTER()
<=Less than equalTo be used with FILTER()
>Greater thanTo be used with FILTER()
>=Greater than equalTo be used with FILTER()
==EqualsTo be used with FILTER()
!=Not equalsTo be used with FILTER()
&Logical andTo be used with FILTER()
|Logical orTo be used with FILTER()
!NegateTo be used with FILTER()

Functions

FunctionDescription
ABS(value)Absolute of value / remove sign
MIN(value1, value2)Minimum of two values
MAX(value1, value2)Maximum of two values
MOD(a, n)Modulo operation
FILTERPORT(value)Retains the value only on port tack (AWA between -170 and -10)
FILTERSTBD(value)Retains the value only on starboard tack (AWA between 10 and 170)
COALESCE(value1, value2)Choose value1 if it’s not empty, else value2
SELECTPORTSTBD(valuePort, valueStbd)Select valuePort when sailing on port tack, valueStbd on starboard tack
MAKEABSOLUTEANGLECONTINUOUS(value)Removes wrap at 0/360 degrees, instead expands value below 0 or above 360 as needed for safe calculations
SHIFT(value, rows)Shifts value (series) by given number of rows
SHIFTSEC(value, seconds)Shifts value (series) by given number of seconds
DELTASEC(value, seconds)Delta of value compared to second seconds ago
DELTAPERSEC(value)Delta of value compared to previous datapoint, divided by number of seconds since last datapoint
ROLLINGMEAN(value, seconds)Rolling mean over second seconds
FILTER(value, mask)Filters value using the given mask, returning empty value where the mask is false
INTERPOLATED(value)Fill blanks between values by linear interpolation
INTERPOLATEDBEARING(value)Fill blanks between values by linear interpolation, correctly handling 0/360 degree wrap around

Note: all function names are case insensitive and may be written in lower case too.

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