Merge pull request #601 from locationtech/fix/mask-double-nodata

Fix: Mask over double tiles uses int NODATA

Author: echeipesh

core/src/main/scala/org/locationtech/rasterframes/expressions/transformers/InverseMaskByDefined.scala

@@ -60,7 +60,7 @@ case class InverseMaskByDefined(targetTile: Expression, maskTile: Expression)
     val (mask, maskCtx) = maskTileExtractor(row(maskInput))
     val result = maskEval(targetTile, mask,
       { (v, m) => if (isNoData(m)) v else NODATA },
-      { (v, m) => if (isNoData(m)) v else NODATA }
+      { (v, m) => if (isNoData(m)) v else Double.NaN }
     )
     toInternalRow(result, targetCtx)
   }

core/src/main/scala/org/locationtech/rasterframes/expressions/transformers/InverseMaskByValue.scala

@@ -73,7 +73,7 @@ case class InverseMaskByValue(targetTile: Expression, maskTile: Expression, mask
 
     val result = maskEval(targetTile, mask,
       { (v, m) => if (m != maskValue) NODATA else v },
-      { (v, m) => if (m != maskValue) NODATA else v }
+      { (v, m) => if (m != maskValue) Double.NaN else v }
     )
     toInternalRow(result, targetCtx)
   }

core/src/main/scala/org/locationtech/rasterframes/expressions/transformers/MaskByDefined.scala

@@ -59,7 +59,7 @@ case class MaskByDefined(targetTile: Expression, maskTile: Expression)
     val (mask, maskCtx) = maskTileExtractor(row(maskInput))
     val result = maskEval(targetTile, mask,
       { (v, m) => if (isNoData(m)) NODATA else v },
-      { (v, m) => if (isNoData(m)) NODATA else v }
+      { (v, m) => if (isNoData(m)) Double.NaN else v }
     )
     toInternalRow(result, targetCtx)
   }

core/src/main/scala/org/locationtech/rasterframes/expressions/transformers/MaskByValue.scala

@@ -73,7 +73,7 @@ case class MaskByValue(targetTile: Expression, maskTile: Expression, maskValue:
 
     val result = maskEval(targetTile, mask,
       { (v, m) => if (m == maskValue) NODATA else v },
-      { (v, m) => if (m == maskValue) NODATA else v }
+      { (v, m) => if (m == maskValue) Double.NaN else v }
     )
     toInternalRow(result, targetCtx)
   }

core/src/main/scala/org/locationtech/rasterframes/expressions/transformers/MaskByValues.scala

@@ -73,7 +73,7 @@ case class MaskByValues(targetTile: Expression, maskTile: Expression, maskValues
 
     val result = maskEval(targetTile, mask,
       { (v, m) => if (maskValues.contains(m)) NODATA else v },
-      { (v, m) => if (maskValues.contains(m)) NODATA else v }
+      { (v, m) => if (maskValues.contains(m)) Double.NaN else v }
     )
 
     toInternalRow(result, targetCtx)

core/src/test/scala/org/locationtech/rasterframes/functions/MaskingFunctionsSpec.scala

@@ -134,6 +134,31 @@ class MaskingFunctionsSpec extends TestEnvironment {
       checkDocs("rf_mask_by_value")
     }
 
+    it("should mask_by_value") {
+      val values = (0 to 16)
+      val tile: Tile = DoubleArrayTile(values.map(_.toDouble).toArray, 4, 4)
+      // array([[ 0,  1,  2,  3],
+      //        [ 4,  5,  6,  7],
+      //        [ 8,  9, 10, 11],
+      //        [12, 13, 14, 15]])
+      val mask: Tile = IntArrayTile(values.map(x => x % 2 * 4).toArray, 4, 4)
+      // array([[0, 4, 0, 4],
+      //        [0, 4, 0, 4],
+      //        [0, 4, 0, 4],
+      //        [0, 4, 0, 4]])
+
+      import spark.implicits._
+      val df = List((tile, mask)).toDF("tile", "mask")
+
+      val (maskedTile, inverseMaskedTile) = df.select(
+        rf_mask_by_value(col("tile"), col("mask"), lit(4), inverse=false).alias("m1"),
+        rf_mask_by_value(col("tile"), col("mask"), lit(4), inverse=true).alias("m2")
+      ).as[(Tile, Tile)].first()
+
+      maskedTile.findMinMax shouldBe (0, 14)
+      inverseMaskedTile.findMinMax shouldBe (1, 15)
+    }
+
     it("should mask by value for value 0.") {
       import spark.implicits._
       // maskingTile has -4, ND, and -15 values. Expect mask by value with 0 to not change the