limited rng seed choice by 5 values in dtree, boost, rtrees, ertrees tests; hope this make them more stable.

tests/ml/src/amltests.cpp

@@ -100,12 +100,17 @@ int CV_AMLTest::validate_test_results( int testCaseIdx )
         resultNode["mean"] >> mean;
         resultNode["sigma"] >> sigma;
         float curErr = get_error( testCaseIdx, CV_TEST_ERROR );
-        if ( abs( curErr - mean) > 6*sigma )
+        const int coeff = 3;
+        ts->printf( CvTS::LOG, "Test case = %d; test error = %f; mean error = %f (diff=%f), %d*sigma = %f",
+                                testCaseIdx, curErr, mean, abs( curErr - mean), coeff, coeff*sigma );
+        if ( abs( curErr - mean) > coeff*sigma )
         {
-            ts->printf( CvTS::LOG, "in test case %d test error is out of range:\n"
+            ts->printf( CvTS::LOG, "abs(%f - %f) > %f - OUT OF RANGE!\n", curErr, mean, coeff*sigma, coeff );
-                                    "abs(%f/*curEr*/ - %f/*mean*/ > %f/*6*sigma*/", testCaseIdx, curErr, mean, 6*sigma );
             return CvTS::FAIL_BAD_ACCURACY;
         }
+        else
+            ts->printf( CvTS::LOG, ".\n" );
+
     }
     else
     {

tests/ml/src/mltest_main.cpp

@@ -45,10 +45,10 @@ CvTS test_system("ml");
 
 const char* blacklist[] =
 {
-    "adtree",          //ticket 662
+    /*"adtree",        //ticket 662
     "artrees",         //ticket 460
     "aboost",          //ticket 474
-    "aertrees",
+    "aertrees",*/      //ticket 505
     0
 };
 

tests/ml/src/mltests.cpp

@@ -432,6 +432,20 @@ int str_to_boost_type( string& str )
 CV_MLBaseTest::CV_MLBaseTest( const char* _modelName, const char* _testName, const char* _testFuncs ) :
 CvTest( _testName, _testFuncs )
 {
+    int64 seeds[] = { 0x00009fff4f9c8d52,
+                      0x0000a17166072c7c,
+                      0x0201b32115cd1f9a,
+                      0x0513cb37abcd1234,
+                      0x0001a2b3c4d5f678
+                    };
+
+    int seedCount = sizeof(seeds)/sizeof(seeds[0]);
+    RNG& rng = theRNG();
+
+    initSeed = rng.state;
+
+    rng.state = seeds[rng(seedCount)];
+
     modelName = _modelName;
     nbayes = 0;
     knearest = 0;
@@ -495,6 +509,7 @@ CV_MLBaseTest::~CV_MLBaseTest()
         delete rtrees;
     if( ertrees )
         delete ertrees;
+    theRNG().state = initSeed;
 }
 
 int CV_MLBaseTest::read_params( CvFileStorage* _fs )