#330 frontend: improved sigmoid and delayed sigmoid functions to be m…

…ore precise
hpi-sam · Sep 16, 2024 · 67910d5 · 67910d5
1 parent 267a9a2
commit 67910d5
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Showing 2 changed files with 8 additions and 22 deletions.
diff --git a/backend/dps_training_k/data/continuous_variables_data.py b/backend/dps_training_k/data/continuous_variables_data.py
@@ -54,7 +54,7 @@ def update_or_create_continuous_variables():
         uuid=ContinuousVariableIDs.HEART_RATE,
         defaults={
             "name": ContinuousVariable.Variable.HEART_RATE,
-            "function": ContinuousVariable.Function.LINEAR,
+            "function": ContinuousVariable.Function.SIGMOID_DELAYED,
             "exceptions": [],
         },
     )
diff --git a/frontend/src/stores/ContinuousVariables.ts b/frontend/src/stores/ContinuousVariables.ts
@@ -111,50 +111,36 @@ function linear(variable: ContinuousVariableInternal, timeUntilPhaseChange: numb
 }
 
 function sigmoid(variable: ContinuousVariableInternal, timeUntilPhaseChange: number): number {
-	// higher value = steeper; higher -> lower infinTargetCorrection
-	const steepness = 10
-	// magic value (try & error for steepness 10/20) needed for correction as the target height is only reached -> infin
-	const infinTargetCorrection = 3.5
+	const steepness = 8 // = the horizontal range that is taken from the original atan function (higher values = steeper)
 
 	const t = variable.tDelta - timeUntilPhaseChange
 	const tMid = variable.tDelta / 2
-
 	const tStretchFactor = 1 / ((Math.pow(variable.tDelta, 2)) / Math.pow(steepness, 2))
-	const tStretchCorrectorNormalizer = Math.atan(Math.sqrt(1) * variable.tDelta) / Math.sqrt(1)
-	const tStretchCorrector = (Math.atan(Math.sqrt(tStretchFactor) * variable.tDelta) / Math.sqrt(tStretchFactor)) / tStretchCorrectorNormalizer
+	const tStretchCorrector = variable.tDelta / steepness
 
-	// original height of atanDerivative fun, - infinTargetCorrection scaled with t_delta
-	const pi = Math.PI - (infinTargetCorrection / variable.tDelta)
 	const xDelta = variable.xTarget - variable.xStart
-	const xStretcher = xDelta / pi
+	const xStretcher = xDelta / (2 * Math.atan(steepness / 2))
 
 	const atanDerivative = (1 / (Math.pow(t - tMid, 2) * tStretchFactor + 1))
 
-	return atanDerivative * xStretcher / tStretchCorrector
+	return (atanDerivative * xStretcher / tStretchCorrector)
 }
 
 function sigmoidDelayed(variable: ContinuousVariableInternal, timeUntilPhaseChange: number): number {
-	// higher value = steeper; higher -> lower infinTargetCorrection
-	const steepness = 10
-	// magic value (try & error for steepness 10/20) needed for correction as the target height is only reached -> infin
-	const infinTargetCorrection = 3.5
+	const steepness = 8 // = the horizontal range that is taken from the original atan function (higher values = steeper)
 
 	const t = variable.tDelta - timeUntilPhaseChange
 	const tMid = variable.tDelta / 2
-
 	const tShiftFrac = 3
 	const t0Shifted = variable.tDelta / tShiftFrac  // Time when sigmoid starts (shifted by one tShiftFrac)
 	const tDeltaShifted = variable.tDelta - t0Shifted
 	const tShiftedMid = tMid + (variable.tDelta - tMid) / tShiftFrac  // Shifted midpoint
 
 	const tStretchFactor = 1 / ((Math.pow(tDeltaShifted, 2)) / Math.pow(steepness, 2))
-	const tStretchCorrectorNormalizer = Math.atan(Math.sqrt(1) * variable.tDelta) / Math.sqrt(1)
-	const tStretchCorrector = (Math.atan(Math.sqrt(tStretchFactor) * variable.tDelta) / Math.sqrt(tStretchFactor)) / tStretchCorrectorNormalizer
+	const tStretchCorrector = tDeltaShifted / steepness
 
-	// original height of atanDerivative fun, - infinTargetCorrection scaled with t_delta
-	const pi = Math.PI - (infinTargetCorrection / tDeltaShifted)
 	const xDelta = variable.xTarget - variable.xStart
-	const xStretcher = xDelta / pi
+	const xStretcher = xDelta / (2 * Math.atan(steepness / 2))
 
 	const atanDerivative = (1 / (Math.pow(t - tShiftedMid, 2) * tStretchFactor + 1))