CalculateVelocity

Short summary

This function can be used to calculate a veloctiy from given distance and time deltas.

Return: the calculated velocity in METER per SECOND

• Return type: Velocity

Parameters

Name	Type	Comment	Kind
distanceDelta	Length	the distance to travel	inout
timeDelta	Duration	the time it needs to travel	inout

Code

Declaration

FUNCTION CalculateVelocity : Velocity
VAR_IN_OUT
	(* the distance to travel *)
	distanceDelta :Length;
	(* the time it needs to travel *)
	timeDelta :Duration; 
END_VAR
VAR
	tmpDistance :Length;
	tmpTime :Duration;
END_VAR

Implementation

RETURN(
		(timeDelta.value = 0.0) // we cannot divide by zero without destroying the universe
	OR_ELSE 
		NOT CheckValueIsANumber(distanceDelta.value)
	OR_ELSE 
		NOT CheckValueIsANumber(timeDelta.value)
);

IF (	(distanceDelta.unit = LengthUnit.METER)
	AND_THEN
		(distanceDelta.prefix = MetricPrefixes.NONE)
	AND_THEN
		(timeDelta.unit = DurationUnit.SECONDS)
	AND_THEN
		(timeDelta.prefix = MetricPrefixes.NONE)
	)
THEN
	CalculateVelocity.value := distanceDelta.value / timeDelta.value;
ELSE
	tmpDistance := ConvertLength(distanceDelta);
	tmpTime := ConvertDuration(timeDelta);
	CalculateVelocity.value := tmpDistance.value / tmpTime.value;
END_IF