I am currently trying to build a workflow in a Real Time Analytic (RTA) that will calculate the running total of material used/spread by a snow plow vehicle over a given event. Each vehicle's AVL data includes a "rate" of material spread and distance traveled using the Odometer (although the distance traveled values are not very accurate). I am using the Calculate Motion Statistics to capture the distance traveled between each track's polled event.
At this time I am able to calculate the material used between each time the vehicle is polled, but I am having trouble building a workflow to capture the running total of material used. I have been able to build a Big Data Analytic to capture the sum total of material used, but this is not 100% what I am looking for. Is it possible to calculate the running total in an RTA? Below is the general workflow I have so far, but does not seem to work.
Calculate Motion Stats --> calculate distance;
- Dist. Tolerance: 10ft
- Timespan Tolerance: 3sec
- Target Time Window: 1 min
- History Depth: 3
- Method: Geodesic
Calculate Fields --> calculate distance moved in miles; convert feet to miles
- calculate material spread between each point? (distance * granular rate)
- granular rate and distance should use same units (feet to feet; miles to miles; etc.)
Map Fields --> map fields to be created in output
- add field for Material Spread Sum --> return 0 (can't return null)
Calculate Fields (2) --> calculate running total of material spread
//GranularMaterialSpread_dist == current material spread (not total)
var currMaterialSpread = $feature.GranularMaterialSpread_dist
var prevMaterialSum = null
if(count(TrackFieldWindow('GranMaterialSum', -1, 0)) < 1){
prevMaterialSum = 0
return (currMaterialSpread + prevMaterialSum)
}
if(count(TrackFieldWindow('GranMaterialSum', -1, 0)) >= 1){
prevMaterialSum = TrackFieldWindow('GranMaterialSum', -1, 0)[0]
return (currMaterialSpread + prevMaterialSum)
}
else{
return -999
}
