[FLINK-13450][table api] Use StrictMath instead of Math for exp

This ensures compatibility of results across processor architectures This closes apache#10432
mbalassi · Dec 6, 2019 · 5545d8a · 5545d8a
1 parent af8b3a8
commit 5545d8a
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Showing 3 changed files with 13 additions and 2 deletions.
diff --git a/...nk-table-planner/src/main/scala/org/apache/flink/table/codegen/calls/BuiltInMethods.scala b/...nk-table-planner/src/main/scala/org/apache/flink/table/codegen/calls/BuiltInMethods.scala
@@ -45,7 +45,7 @@ object BuiltInMethods {
 
  val LOG2 = Types.lookupMethod(classOf[ScalarFunctions], "log2", classOf[Double])
 
- val EXP = Types.lookupMethod(classOf[Math], "exp", classOf[Double])
+ val EXP = Types.lookupMethod(classOf[ScalarFunctions], "exp", classOf[Double])
 
  val POWER = Types.lookupMethod(classOf[Math], "pow", classOf[Double], classOf[Double])
  val POWER_DEC = Types.lookupMethod(

diff --git a/...ble-planner/src/main/scala/org/apache/flink/table/runtime/functions/ScalarFunctions.scala b/...ble-planner/src/main/scala/org/apache/flink/table/runtime/functions/ScalarFunctions.scala
@@ -115,6 +115,17 @@ object ScalarFunctions {
  }
  }
 
+ /**
+ * Returns exp(x).
+ */
+ def exp(x: Double): Double = {
+ if (x <= 0.0) {
+ throw new IllegalArgumentException(s"x of 'exp(x)' must be > 0, but x = $x")
+ } else {
+ StrictMath.exp(x)
+ }
+ }
+
  /**
  * Calculates the hyperbolic tangent of a big decimal number.
  */

diff --git a/...k-table-planner/src/test/scala/org/apache/flink/table/expressions/SqlExpressionTest.scala b/...k-table-planner/src/test/scala/org/apache/flink/table/expressions/SqlExpressionTest.scala
@@ -104,7 +104,7 @@ class SqlExpressionTest extends ExpressionTestBase {
  testSqlApi("LOG2(8)", "3.0")
  testSqlApi("LOG(E())", "1.0")
  testSqlApi("LOG(3,27)", "3.0000000000000004")
- testSqlApi("EXP(1)", "2.718281828459045")
+ testSqlApi("EXP(1)", "2.7182818284590455")
  testSqlApi("CEIL(2.5)", "3")
  testSqlApi("CEILING(2.5)", "3")
  testSqlApi("FLOOR(2.5)", "2")