interpolation.cpp File Reference

Detailed Description

Linear interpolation algorithms.

See test_interpolation_3d.cpp

Date

Oct 17, 2013

Author

Andrey Belomutskiy, (c) 2012-2020

Dmitry Sidin, (c) 2015

Definition in file interpolation.cpp.

Functions
float	interpolateMsg (const char *msg, float x1, float y1, float x2, float y2, float x)
	Linear interpolation by two points.
float	interpolateClampedWithValidation (float x1, float y1, float x2, float y2, float x)
float	interpolateClamped (float x1, float y1, float x2, float y2, float x)

Function Documentation

interpolateClamped()

float interpolateClamped	(	float	x1,
		float	y1,
		float	x2,
		float	y2,
		float	x
	)

todo: use 'interpolateClampedWithValidation' wider?

See also

interpolateMsg

Definition at line 69 of file interpolation.cpp.

                                                                          {
    // note how we assume order of x1 and x2 here! see also interpolateClampedWithValidation
    if (x <= x1)
        return y1;
    if (x >= x2)
        return y2;
 
    // todo: do we care with code duplication with interpolateMsg above?
    float a = INTERPOLATION_A(x1, y1, x2, y2);
    float b = y1 - a * x1;
    return a * x + b;
}

Referenced by LaunchControlBase::calculateSparkSkipRatio(), ThrottleModelBase::estimateThrottleFlow(), flexCallback(), IdleController::getClosedLoop(), getCrankingAdvance(), getCrankingFuel3(), IdleController::getIdleTimingAdjustment(), IdleController::getOpenLoop(), getRunningAdvance(), IdleController::getRunningOpenLoop(), EtbController::getSetpointEtb(), FuelComputer::getStoichiometricRatio(), IdleController::getTargetRpm(), IFuelComputer::getTCharge(), IFuelComputer::getTChargeCoefficient(), DfcoController::getTimingRetard(), AirmassVeModelBase::getVe(), interpolateClampedWithValidation(), HellaOilLevelSensor::onEdge(), setHysteresis(), LimpManager::updateRevLimit(), and updateVrThresholdPwm().

Here is the caller graph for this function:

interpolateClampedWithValidation()

float interpolateClampedWithValidation	(	float	x1,
		float	y1,
		float	x2,
		float	y2,
		float	x
	)

Definition at line 58 of file interpolation.cpp.

                                                                                        {
    if (x1 >= x2) {
        criticalError("interpolateClamped %f has to be smaller than %f", x1, x2);
    }
    return interpolateClamped(x1, y1, x2, y2, x);
}

Here is the call graph for this function:

interpolateMsg()

float interpolateMsg	(	const char *	msg,
		float	x1,
		float	y1,
		float	x2,
		float	y2,
		float	x
	)

Linear interpolation by two points.

Parameters

x1	key of the first point
y1	value of the first point
x2	key of the second point
y2	value of the second point
X	key to be interpolated

Note

For example, "interpolateMsg("", engineConfiguration.tpsMin, 0, engineConfiguration.tpsMax, 100, adc);"

See also

interpolateClamped

we could end up here for example while resetting bins while changing engine type

Definition at line 28 of file interpolation.cpp.

                                                                                       {
    if (std::isnan(x1) || std::isnan(x2) || std::isnan(y1) || std::isnan(y2)) {
        warning(ObdCode::CUSTOM_ERR_INTERPOLATE_1, "interpolate%s: why param", msg);
        return NAN;
    }
    if (std::isnan(x)) {
        warning(ObdCode::CUSTOM_ERR_INTERPOLATE_2, "interpolate%s: why X", msg);
        return NAN;
    }
    // todo: double comparison using EPS
    if (x1 == x2) {
        /**
         * we could end up here for example while resetting bins while changing engine type
         */
        warning(ObdCode::CUSTOM_ERR_INTERPOLATE_3, "interpolate%s: Same x1 and x2 in interpolate: %.2f/%.2f", msg, x1, x2);
        return NAN;
    }
 
    // a*x1 + b = y1
    // a*x2 + b = y2
//  efiAssertVoid(ObdCode::CUSTOM_ERR_ASSERT_VOID, x1 != x2, "no way we can interpolate");
    float a = INTERPOLATION_A(x1, y1, x2, y2);
    if (std::isnan(a)) {
        warning(ObdCode::CUSTOM_ERR_INTERPOLATE_4, "interpolate%s: why a", msg);
        return NAN;
    }
    float b = y1 - a * x1;
    return a * x + b;
}

Referenced by decodeTpsSentValue(), getAdvanceForRpm(), getAfr(), IFuelComputer::getTChargeCoefficient(), lua_interpolate(), and setLinearCurve().

Here is the call graph for this function:

Here is the caller graph for this function:

Go to the source code of this file.