Fix to the quicksort algorithm in the percentile extension.

FossilOrigin-Name: 54313f74b24c46f1afa1ff082ef569fa46938527095be358015e7047e17702ac

diff --git a/ext/misc/percentile.c b/ext/misc/percentile.c
index 3e619db69e8acd43092d0d44c5d72c2dc2c9e978..718be80da694209749a5131d398be47a64346797 100644 (file)
--- a/ext/misc/percentile.c
+++ b/ext/misc/percentile.c
@@ -292,7 +292,12 @@ static void sortDoubles(double *a, int n){
 
   if( n<2 ) return;
   if( n>5 ){
-    rPivot = (a[0] + a[n/2] + a[n-1])/3.0;
+    double x[3];
+    x[0]= a[0];
+    x[1] = a[n/2];
+    x[2] = a[n-1];
+    sortDoubles(x,3);
+    rPivot = x[1];
   }else{
     rPivot = a[n/2];
   }

diff --git a/manifest b/manifest
index 1eec821886cfb89bd4aea81ac479434c0d2981b0..ce1c02895233dd1a568ac77e5a0314b8ca6beebb 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Include\spercentile()\sand\smerge()\sin\sthe\sfuzzcheck\stest\sutility.
-D 2024-08-31T19:24:17.689
+C Fix\sto\sthe\squicksort\salgorithm\sin\sthe\spercentile\sextension.
+D 2024-09-01T10:52:20.432
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -410,7 +410,7 @@ F ext/misc/nextchar.c 7877914c2a80c2f181dd04c3dbef550dfb54c93495dc03da2403b5dd58
 F ext/misc/noop.c f1a21cc9b7a4e667e5c8458d80ba680b8bd4315a003f256006046879f679c5a0
 F ext/misc/normalize.c bd84355c118e297522aba74de34a4fd286fc775524e0499b14473918d09ea61f
 F ext/misc/pcachetrace.c f4227ce03fb16aa8d6f321b72dd051097419d7a028a9853af048bee7645cb405
-F ext/misc/percentile.c ea1ff3561374c520193d5c3b3c86a40d922a9f0c2b48ae784d6cd9490093bd9d
+F ext/misc/percentile.c c5ddb86314a0648c510de54a7290b939225b128925d98b02859c47d98f9ec282
 F ext/misc/prefixes.c 82645f79229877afab08c8b08ca1e7fa31921280906b90a61c294e4f540cd2a6
 F ext/misc/qpvtab.c fc189e127f68f791af90a487f4460ec91539a716daf45a0c357e963fd47cc06c
 F ext/misc/randomjson.c ef835fc64289e76ac4873b85fe12f9463a036168d7683cf2b773e36e6262c4ed
@@ -1517,7 +1517,7 @@ F test/parser1.test 6ccdf5e459a5dc4673d3273dc311a7e9742ca952dd0551a6a6320d27035c
 F test/pcache.test c8acbedd3b6fd0f9a7ca887a83b11d24a007972b
 F test/pcache2.test af7f3deb1a819f77a6d0d81534e97d1cf62cd442
 F test/pendingrace.test e99efc5ab3584da3dfc8cd6a0ec4e5a42214820574f5ea24ee93f1d84655f463
-F test/percentile.test 96b941965a5e5dff7c7d0d31c099385324897a692a300a4c4370b2fb760e7dd0
+F test/percentile.test 5c5b622035d5e2e9a23e8462b2f59f9f9364e736f3ddfb0ffe294b1854f9caad
 F test/permutations.test 405542f1d659942994a6b38a9e024cf5cfd23eaa68c806aeb24a72d7c9186e80
 F test/pg_common.tcl 3b27542224db1e713ae387459b5d117c836a5f6e328846922993b6d2b7640d9f
 F test/pragma.test 11cb9310c42f921918f7f563e3c0b6e70f9f9c3a6a1cf12af8fccb6c574f3882
@@ -2211,8 +2211,8 @@ F vsixtest/vsixtest.tcl 6195aba1f12a5e10efc2b8c0009532167be5e301abe5b31385638080
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 3fe0a852978f3f1218e37a58f0d3b54016d4116a3301aa32efa7c4c12c767755
-R fe4924b06f0c2e628905b36a4804a9df
+P d1d0942a947803d45a1fd9068f3518cf412178b6b9bafcb82db44c52d5820c11
+R 8b4bddb09aaccc6a2b060f365f91dbd1
 U drh
-Z f104fe8dff33191117d210e31173232d
+Z 1fbd72dda73eb1323c7b4878ebf0259d
 # Remove this line to create a well-formed Fossil manifest.

diff --git a/manifest.uuid b/manifest.uuid
index a1cdbd5ba6b5f675bb84066c070870e296e4ed3d..67c2b6b8868db64bfb7c0e921715385009c8c37f 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-d1d0942a947803d45a1fd9068f3518cf412178b6b9bafcb82db44c52d5820c11
+54313f74b24c46f1afa1ff082ef569fa46938527095be358015e7047e17702ac

diff --git a/test/percentile.test b/test/percentile.test
index 14e40714b06657518341db90963c1a0b7e48e980..cef3835957435555b496d0d5153ab0df2af7f6cf 100644 (file)
--- a/test/percentile.test
+++ b/test/percentile.test
@@ -358,6 +358,10 @@ do_execsql_test percentile-5.1 {
   Emma   Z  2319.99  699.1    1104.3225  1509.545  1914.7675  2319.99
 }
 
-
+# Fuzzer find.
+do_execsql_test percentile-6.0 {
+  WITH RECURSIVE c(n) AS (VALUES(1) UNION ALL SELECT n+1 FROM c WHERE n<12)
+  SELECT median(iif(n%2,0.1,1.0)) FROM c;
+} 0.55
 
 finish_test