FSX Fast Slow Indicator

[Doia]

Has anybody figured out how to do a Fast/Slow Indicator? Would it be just the same thing as a trend indicator?
The only reason I am not sure is because I believe the angle of attack should be accounted for and yet I don't see it being used in any trend indicators samples I currently have.
I found this trend indicator posted by Fr. Bill on Avsim Forums but there is no reference to angle of attack.

<!-- ======================= AIRSPEED TREND INDICATOR ======================= -->
<Element>
    <Select>
        <Value>
            (P:Local Time, seconds) 0.2 % 10 * int 0 == 
            if{ (A:Airspeed select indicated or true, knots) (>L:SpeedPrevious,knot) }
        </Value>
    </Select>
</Element>

<Element>
    <Select>
        <Value>
            (P:Local Time, seconds) 0.2 % 10 * int 1 == 
            if{ (A:Airspeed select indicated or true, knots) s1 (L:SpeedPrevious,knot) - 0.1 / 10 * l1 + (>L:SpeedTrend,knot) }
        </Value>
    </Select>
</Element>

<Element>
    <Position X="275" Y="145"/>
    <Visible>
        (L:SpeedTrend,knot) (A:Airspeed select indicated or true, knots) &gt;
    </Visible>
    <MaskImage Name="G1000_SpeedTrend_Mask.bmp" Bright="Yes">
        <Axis X="0" Y="64"/>
    </MaskImage>
    <Image Name="G1000_SpeedTrend.bmp" Bright="Yes">
        <Nonlinearity>
            <Item Value="2" X="0" Y="0"/>
            <Item Value="40" X="0" Y="64"/>
        </Nonlinearity>
    </Image>
    <Shift>
        <Value Minimum="2" Maximum="40">
            (A:Airspeed select indicated or true, knots) 45 &lt; 
            if{ 0 } 
            els{ (L:SpeedTrend,knot) (A:Airspeed select indicated or true, knots) - }
        </Value>
        <Delay PixelsPerSecond="10"/>
    </Shift>
</Element>

<Element>
    <Position X="275" Y="209"/>
    <Visible>
        (L:SpeedTrend,knot) (A:Airspeed select indicated or true, knots) &lt;
    </Visible>
    <MaskImage Name="G1000_SpeedTrend_Mask.bmp" Bright="Yes">
        <Axis X="0" Y="0"/>
    </MaskImage>
    <Image Name="G1000_SpeedTrend.bmp" Bright="Yes">
        <Nonlinearity>
            <Item Value="-2" X="0" Y="64"/>
            <Item Value="-40" X="0" Y="0"/>
        </Nonlinearity>
    </Image>
    <Shift>
        <Value Minimum="-40" Maximum="-2">
            (A:Airspeed select indicated or true, knots) 45 &lt; 
            if{ 0 } 
            els{ (L:SpeedTrend,knot) (A:Airspeed select indicated or true, knots) - }
        </Value>
        <Delay PixelsPerSecond="10"/>
    </Shift>
</Element>

Any help is much appreciated!

Doia

 

[Doia]

Sampling rate?

Okay so I figured the Fast Slow indicator should be pointing to zero if INCIDENCE ALPHA is equal to .65*STALL ALPHA. If it's greater then points to fast, if it's less it points to slow. Here's what I have so far:

<Element id="Define FastSlowInd">
            <FloatPosition>0.000,0.000</FloatPosition>
            <Select id="Select">
                <Expression id="Expression">
                    <Script>
(INCIDENCE ALPHA, radians) (STALL ALPHA, radians) 0.65 * &gt; if { -1 (&gt;L:FastSlowInd, number) } 
(INCIDENCE ALPHA, radians) (STALL ALPHA, radians) 0.65 * == if { 0 (&gt;L:FastSlowInd, number) 
(INCIDENCE ALPHA, radians) (STALL ALPHA, radians) 0.65 * &lt; if { 1 (&gt;L:FastSlowInd, number) }
	      </Script>
                </Expression>
            </Select>
        </Element>
<Element id="Fast Slow Indicator">
            <FloatPosition>114.000,401.000</FloatPosition>
            <Image id="Image" Name="fs_indicator.bmp">
                <Transparent>True</Transparent>
                <Axis>0,0</Axis>
            </Image>
            <Shift id="Shift">
                <Scale>0.000,0.000</Scale>
                <Expression id="Expression">
	      <Minimum>-1.000</Minimum>
                    <Maximum>1.000</Maximum>
                    <Script>
		(L: FastSlowInd, number)
	      </Script>
                </Expression>
                <NonlinearityTable id="NonlinearityTable">
                         <NonlinearityEntry id="Lower Limit">
                        <ExpressionResult>-1</ExpressionResult>
                        <FloatPosition>114.000,490.000</FloatPosition>
                        </NonlinearityEntry>
                         <NonlinearityEntry id="Zero">
                        <ExpressionResult>0</ExpressionResult>
                        <FloatPosition>114.000,401.000</FloatPosition>
                        </NonlinearityEntry>
                        <NonlinearityEntry id="Upper Limit">
                        <ExpressionResult>1</ExpressionResult>
                        <FloatPosition>114.000,317.000</FloatPosition>
                        </NonlinearityEntry>
                </NonlinearityTable>
            </Shift>
</Element>

My indicator is permanently stuck at zero.
I don't know if has anything to do with a sampling rate or if my script is just plain wrong.

I know... I am a newbie - I keep posting my problems and can't answer anybody else's questions - but any help is welcomed

 

[Doia]

ok I feel really retarded. I used a simple INCIDENCE ALPHA/ STALL ALPHA in the the Shift Script

<Script>
    (A:INCIDENCE ALPHA, degrees) (A:STALL ALPHA, degrees) /
</Script>

and then calibrated the translation using nonlinearity (in which 0.65 is the middle neutral position)... really simple don't know why I didn't see it earlier