From a876ddbae5c39827d0ad70c7a74807d206073d10 Mon Sep 17 00:00:00 2001
From: Carlos Quiroz <carlos.quiroz@noirlab.edu>
Date: Mon, 5 Aug 2024 12:50:42 -0400
Subject: [PATCH] Remove the fallbackAirmass concept

---
 .../lucuma/core/math/skycalc/package.scala      |  4 +---
 .../math/skycalc/ImprovedSkyCalcSuiteJVM.scala  | 17 +----------------
 2 files changed, 2 insertions(+), 19 deletions(-)

diff --git a/modules/core/shared/src/main/scala/lucuma/core/math/skycalc/package.scala b/modules/core/shared/src/main/scala/lucuma/core/math/skycalc/package.scala
index 7f793eba..77a6efb5 100644
--- a/modules/core/shared/src/main/scala/lucuma/core/math/skycalc/package.scala
+++ b/modules/core/shared/src/main/scala/lucuma/core/math/skycalc/package.scala
@@ -35,7 +35,6 @@ def parallacticAngle(place: Place, tracking: ObjectTracking, vizTime: Instant):
   * @param tracking object coordinates and motion for the object
   * @param vizTime the time at which the observation is scheduled to start
   * @param duration the duration of the observation
-  * @param fallbackAirmass the airmass to use when the airmass is not available
   * @param samplingRate the rate at which to sample the parallactic angle
   */
 def averageParallacticAngle(
@@ -43,7 +42,6 @@ def averageParallacticAngle(
   tracking: ObjectTracking,
   vizTime: Instant,
   duration: TimeSpan,
-  fallbackAirmass: Double = 0.0,
   samplingRate: TimeSpan = TimeSpan.unsafeFromMicroseconds(30.seconds.toMicros)
 ): Option[Angle] = {
   val defined: TimeRange = (vizTime.toEpochMilli(), vizTime.plus(duration.toDuration).toEpochMilli())
@@ -101,7 +99,7 @@ def averageParallacticAngle(
             angle + normalizingFactor
           } else angle
 
-        val weight = if (airmass <= 0.0) fallbackAirmass else math.pow(airmass - 1.0, 1.3)
+        val weight = if (airmass <= 0.0) 0.0 else math.pow(airmass - 1.0, 1.3)
         (normalizedAngle * weight, weight)
       }
       .unzip
diff --git a/modules/tests/jvm/src/test/scala/lucuma/core/math/skycalc/ImprovedSkyCalcSuiteJVM.scala b/modules/tests/jvm/src/test/scala/lucuma/core/math/skycalc/ImprovedSkyCalcSuiteJVM.scala
index 18b716d4..2bdf398e 100644
--- a/modules/tests/jvm/src/test/scala/lucuma/core/math/skycalc/ImprovedSkyCalcSuiteJVM.scala
+++ b/modules/tests/jvm/src/test/scala/lucuma/core/math/skycalc/ImprovedSkyCalcSuiteJVM.scala
@@ -3,7 +3,6 @@
 
 package lucuma.core.math.skycalc
 
-import cats.syntax.all.*
 import com.fortysevendeg.scalacheck.datetime.GenDateTime.genDateTimeWithinRange
 import com.fortysevendeg.scalacheck.datetime.instances.jdk8.*
 import edu.gemini.skycalc.ImprovedSkyCalcTest
@@ -38,7 +37,7 @@ final class ImprovedSkyCalcSuiteJVM extends ScalaCheckSuite {
   )
   private val zdtRange = Duration.ofDays(Period.ofYears(1000).getDays.toLong)
 
-  test("average parallactic angle no fallback") {
+  test("average parallactic angle no visible target") {
     val when = Instant.parse("2024-08-02T21:00:00Z")
     val coord = Coordinates.fromHmsDms.getOption("00:15:21.550600 +28:35:13.831766").get
     assert(averageParallacticAngle(
@@ -47,20 +46,6 @@ final class ImprovedSkyCalcSuiteJVM extends ScalaCheckSuite {
       when,
       TimeSpan.fromHours(1).get).isEmpty
     )
-
-  }
-
-  test("average parallactic angle with fallback") {
-    val when = Instant.parse("2024-08-02T21:00:00Z")
-    val coord = Coordinates.fromHmsDms.getOption("00:15:21.550600 +28:35:13.831766").get
-    assert(averageParallacticAngle(
-      Site.GN.place,
-      ObjectTracking.constant(coord),
-      when,
-      TimeSpan.fromHours(1).get,
-      100).exists(_ === Angle.fromMicroarcseconds(216766799171L))
-    )
-
   }
 
   test("Arbitrary sky calculations".tag(ScalaCheckFlaky)) {