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From desruisse...@apache.org
Subject svn commit: r1805428 - /sis/branches/JDK8/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/projection/EqualAreaProjection.java
Date Fri, 18 Aug 2017 13:48:52 GMT
Author: desruisseaux
Date: Fri Aug 18 13:48:51 2017
New Revision: 1805428

URL: http://svn.apache.org/viewvc?rev=1805428&view=rev
Log:
Enable the user of trigonometric identities for performance.

Modified:
    sis/branches/JDK8/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/projection/EqualAreaProjection.java

Modified: sis/branches/JDK8/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/projection/EqualAreaProjection.java
URL: http://svn.apache.org/viewvc/sis/branches/JDK8/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/projection/EqualAreaProjection.java?rev=1805428&r1=1805427&r2=1805428&view=diff
==============================================================================
--- sis/branches/JDK8/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/projection/EqualAreaProjection.java
[UTF-8] (original)
+++ sis/branches/JDK8/core/sis-referencing/src/main/java/org/apache/sis/referencing/operation/projection/EqualAreaProjection.java
[UTF-8] Fri Aug 18 13:48:51 2017
@@ -54,13 +54,15 @@ abstract class EqualAreaProjection exten
      *
      *
      * <p><b>BENCHMARK AND ANALYSIS:</b>
-     * as of July 2016, benchmarking shows no benefit in using trigonometric identities for
{@code EqualAreaProjection}
-     * (contrarily to {@link ConformalProjection} where we did measured a benefit). This
may be because in this class,
+     * as of July 2016, benchmarking shows small benefit in using trigonometric identities
for {@code EqualAreaProjection}
+     * (contrarily to {@link ConformalProjection} where we measured a greater benefit). This
may be because in this class,
      * the series expansion is unconditionally followed by iterative method in order to reach
the centimetric precision.
      * We observe that the original series expansion allows convergence in only one iteration,
while the formulas using
-     * trigonometric identifies often requires two iterations. Consequently we disallow those
modifications for now.</p>
+     * trigonometric identifies often requires two iterations.</p>
+     *
+     * @todo Redo the benchmark with JDK9, since {@code sin} seems much faster.
      */
-    private static final boolean ALLOW_TRIGONOMETRIC_IDENTITIES = false;
+    private static final boolean ALLOW_TRIGONOMETRIC_IDENTITIES = true;
 
     /**
      * Coefficients in the series expansion of the inverse projection,



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