LoopkitPatch.txt

diff --git a/LoopKit/InsulinKit/InsulinMath.swift b/LoopKit/InsulinKit/InsulinMath.swift
index 6efd2bd..094fee4 100644
--- a/LoopKit/InsulinKit/InsulinMath.swift
+++ b/LoopKit/InsulinKit/InsulinMath.swift
@@ -40,10 +40,23 @@ extension DoseEntry {
         }
 
         // Consider doses within the delta time window as momentary
+        //ken changes
+        //implement user set negative basal multiplier
+        var negativeBasalMultiplier = UserDefaults.standard.double(forKey: "negativeBasalMultiplier")
+        // if user has not modified settings, this value reports as 0 initially
+        // Default shows as 100%, aka, same as unmodified code
+        if negativeBasalMultiplier == 0 {
+            negativeBasalMultiplier = 1
+        }
+        var modifiednetBasalUnits = netBasalUnits
+        if netBasalUnits < 0.0 {
+            modifiednetBasalUnits = netBasalUnits * negativeBasalMultiplier
+        }
+        //this used netBasalUnits as multiplier originally
         if endDate.timeIntervalSince(startDate) <= 1.05 * delta {
-            return netBasalUnits * model.percentEffectRemaining(at: time)
+            return modifiednetBasalUnits * model.percentEffectRemaining(at: time)
         } else {
-            return netBasalUnits * continuousDeliveryInsulinOnBoard(at: date, model: model, delta: delta)
+            return modifiednetBasalUnits * continuousDeliveryInsulinOnBoard(at: date, model: model, delta: delta)
         }
     }
 
@@ -77,11 +90,23 @@ extension DoseEntry {
         }
 
         // Consider doses within the delta time window as momentary
-        if endDate.timeIntervalSince(startDate) <= 1.05 * delta {
-            return netBasalUnits * -insulinSensitivity * (1.0 - model.percentEffectRemaining(at: time))
-        } else {
-            return netBasalUnits * -insulinSensitivity * continuousDeliveryGlucoseEffect(at: date, model: model, delta: delta)
-        }
+        //ken changes
+            //if net basal is negative use a mulitplier (0-1)
+            //modified in user settings
+            var negativeBasalMultiplier = UserDefaults.standard.double(forKey: "negativeBasalMultiplier")
+            if negativeBasalMultiplier == 0 {
+                negativeBasalMultiplier = 1
+            }
+            var modifiednetBasalUnits = netBasalUnits
+            if netBasalUnits < 0.0 {
+                modifiednetBasalUnits = netBasalUnits * negativeBasalMultiplier
+            }
+            //originally used netBasalUnits
+            if endDate.timeIntervalSince(startDate) <= 1.05 * delta {
+                return modifiednetBasalUnits * -insulinSensitivity * (1.0 - model.percentEffectRemaining(at: time))
+            } else {
+                return modifiednetBasalUnits * -insulinSensitivity * continuousDeliveryGlucoseEffect(at: date, model: model, delta: delta)
+            }
     }
 
     func trimmed(from start: Date? = nil, to end: Date? = nil, syncIdentifier: String? = nil) -> DoseEntry {