array_mode new parameter merge

- array_mode new parameter merge for return value behaviour - updated expression documentation for array_mode, majority and minority - updated tests
qgis · Feb 4, 2021 · a9edb93 · a9edb93
1 parent 7345c12
commit a9edb93
Show file tree

Hide file tree

Showing 5 changed files with 38 additions and 14 deletions.
diff --git a/resources/function_help/json/array_majority b/resources/function_help/json/array_majority
@@ -2,7 +2,7 @@
   "name": "array_majority",
   "type": "function",
   "groups": ["Arrays"],
-  "description": "Returns the value which has majority in the array. Majority means the count of the value is greather than half the size of the array.",
+  "description": "Returns the value which has majority in the array. Majority means the count of the value is greather than half the size of the array.</p><p><b>Note</b><br/>For the same behaviour of the majority() function from Aggregates see array_mode().</p>",
   "arguments": [ {"arg":"array","description":"an array"} ],
   "examples": [
     { "expression":"array_majority(array(0,1,42,42,43))", "returns":"NULL"},

diff --git a/resources/function_help/json/array_minority b/resources/function_help/json/array_minority
@@ -2,7 +2,7 @@
   "name": "array_minority",
   "type": "function",
   "groups": ["Arrays"],
-  "description": "Returns an array containing the minority values in an array. All values are minority exept the majority value if available.",
+  "description": "Returns an array containing the minority values of a given array. All values are minority exept the majority value, if available.",
   "arguments": [ {"arg":"array","description":"an array"} ],
   "examples": [
     { "expression":"array_minority(array(0,1,42,42,43))", "returns":"[ 0, 1, 42, 43 ]"},

diff --git a/resources/function_help/json/array_mode b/resources/function_help/json/array_mode
@@ -2,10 +2,15 @@
   "name": "array_mode",
   "type": "function",
   "groups": ["Arrays"],
-  "description": "Returns an array containing the most common value in an array. The returned array may contain more than one value if multiple values occur equally often.",
-  "arguments": [ {"arg":"array","description":"an array"} ],
+  "description": "Return the most common values in an array. The returned array may contain more than one value if multiple values occur equally often.",
+  "arguments": [
+    {"arg":"array","description":"an array"},
+    {"arg":"merge='all'", "optional":true, "description":"a string specifyng the return values handling. By default all values are returned in an array. Valid options are:<br /><ul><li>all</li><li>first</li><li>median</li></ul>"}
+  ],
   "examples": [
     { "expression":"array_mode(array(0,1,42,42,43))", "returns":"[ 42 ]"},
-    { "expression":"array_mode(array(0,0,1,2,2,42))", "returns":"[ 0, 2 ]"}
+    { "expression":"array_mode(array(0,0,1,2,2,42))", "returns":"[ 0, 2 ]"},
+    { "expression":"array_mode(array(0,1,42,42,43), 'first')", "returns":"42"},
+    { "expression":"array_mode(array(0,1,1,2,2,42), 'median')", "returns":"1.5"}
   ]
 }
diff --git a/src/core/expression/qgsexpressionfunction.cpp b/src/core/expression/qgsexpressionfunction.cpp
@@ -5441,7 +5441,7 @@ static QVariant convertToSameType( const QVariant &value, QVariant::Type type )
   return result;
 }
 
-static QVariant fcnArrayMode( const QVariantList &values, const QgsExpressionContext *, QgsExpression *parent, const QgsExpressionNodeFunction * )
+static QVariant fcnArrayMode( const QVariantList &values, const QgsExpressionContext *context, QgsExpression *parent, const QgsExpressionNodeFunction *node )
 {
   const QVariantList list = QgsExpressionUtils::getListValue( values.at( 0 ), parent );
   QHash< QVariant, int > hash;
@@ -5451,7 +5451,28 @@ static QVariant fcnArrayMode( const QVariantList &values, const QgsExpressionCon
   }
   const QList< int > occurrences = hash.values();
   const int maxValue = *std::max_element( occurrences.constBegin(), occurrences.constEnd() );
-  return convertToSameType( list.isEmpty() ? QVariant() : hash.keys( maxValue ), values.at( 0 ).type() );
+
+  if ( hash.keys( maxValue ).isEmpty() )
+    return QVariant();
+
+  const QString merge = values.at( 1 ).toString();
+  if ( merge.compare( QLatin1String( "all" ), Qt::CaseInsensitive ) == 0 )
+  {
+    return convertToSameType( hash.keys( maxValue ), values.at( 0 ).type() );
+  }
+  else if ( merge.compare( QLatin1String( "first" ), Qt::CaseInsensitive ) == 0 )
+  {
+    return QVariant( hash.keys( maxValue ).first() );
+  }
+  else if ( merge.compare( QLatin1String( "median" ), Qt::CaseInsensitive ) == 0 )
+  {
+    return fcnArrayMedian( QVariantList() << convertToSameType( hash.keys( maxValue ), values.at( 0 ).type() ), context, parent, node );
+  }
+  else
+  {
+    parent->setEvalErrorString( QObject::tr( "No such merge behaviour '%1'" ).arg( merge ) );
+    return QVariant();
+  }
 }
 
 static QVariant fcnArrayMajority( const QVariantList &values, const QgsExpressionContext *, QgsExpression *parent, const QgsExpressionNodeFunction * )
@@ -7101,7 +7122,7 @@ const QList<QgsExpressionFunction *> &QgsExpression::Functions()
         << new QgsStaticExpressionFunction( QStringLiteral( "array_max" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "array" ) ), fcnArrayMaximum, QStringLiteral( "Arrays" ) )
         << new QgsStaticExpressionFunction( QStringLiteral( "array_mean" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "array" ) ), fcnArrayMean, QStringLiteral( "Arrays" ) )
         << new QgsStaticExpressionFunction( QStringLiteral( "array_median" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "array" ) ), fcnArrayMedian, QStringLiteral( "Arrays" ) )
-        << new QgsStaticExpressionFunction( QStringLiteral( "array_mode" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "array" ) ), fcnArrayMode, QStringLiteral( "Arrays" ) )
+        << new QgsStaticExpressionFunction( QStringLiteral( "array_mode" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "array" ) ) << QgsExpressionFunction::Parameter( QStringLiteral( "merge" ), true, QVariant( "all" ) ), fcnArrayMode, QStringLiteral( "Arrays" ) )
         << new QgsStaticExpressionFunction( QStringLiteral( "array_majority" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "array" ) ), fcnArrayMajority, QStringLiteral( "Arrays" ) )
         << new QgsStaticExpressionFunction( QStringLiteral( "array_minority" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "array" ) ), fcnArrayMinority, QStringLiteral( "Arrays" ) )
         << new QgsStaticExpressionFunction( QStringLiteral( "array_sum" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "array" ) ), fcnArraySum, QStringLiteral( "Arrays" ) )

diff --git a/tests/src/core/testqgsexpression.cpp b/tests/src/core/testqgsexpression.cpp
@@ -1661,25 +1661,23 @@ class TestQgsExpression: public QObject
       QTest::newRow( "array_median(array())" ) << QStringLiteral( "array_median(array())" ) << false << QVariant();
       QTest::newRow( "array_median(array(0,1,42,42,43))" ) << QStringLiteral( "array_median(array(0,1,42,42,43))" ) << false << QVariant( 42 );
       QTest::newRow( "array_median(array(0,0,1,2,2,42,'a','b'))" ) << QStringLiteral( "array_median(array(0,0,1,2,2,42,'a','b'))" ) << false << QVariant( 1.5 );
-
       QTest::newRow( "array_mode('forty two')" ) << QStringLiteral( "array_mode('forty two')" ) << true << QVariant();
       QTest::newRow( "array_mode(42)" ) << QStringLiteral( "array_mode(42)" ) << true << QVariant();
       QTest::newRow( "array_mode(array())" ) << QStringLiteral( "array_mode(array())" ) << false << QVariant();
       QTest::newRow( "array_mode(array(1,2,42,42,'a','b'))" ) << QStringLiteral( "array_mode(array(1,2,42,42,'a','b'))" ) << false << QVariant( QVariantList() << 42 );
-
+      QTest::newRow( "array_mode(array(0,1,42,42,43), 'first')" ) << QStringLiteral( "array_mode(array(0,1,42,42,43), 'first')" ) << false << QVariant( 42 );
+      QTest::newRow( "array_mode(array(0,1,1,2,2,42), 'median')" ) << QStringLiteral( "array_mode(array(0,1,1,2,2,42), 'median')" ) << false << QVariant( 1.5 );
       QTest::newRow( "array_majority('forty two')" ) << QStringLiteral( "array_majority('forty two')" ) << true << QVariant();
       QTest::newRow( "array_majority(42)" ) << QStringLiteral( "array_majority(42)" ) << true << QVariant();
       QTest::newRow( "array_majority(array())" ) << QStringLiteral( "array_majority(array())" ) << false << QVariant();
       QTest::newRow( "array_majority(array(0,1,42,42,43))" ) << QStringLiteral( "array_majority(array(0,1,42,42,43))" ) << false << QVariant();
       QTest::newRow( "array_majority(array(0,1,42,42,43,42))" ) << QStringLiteral( "array_majority(array(0,1,42,42,43,42))" ) << false << QVariant();
       QTest::newRow( "array_majority(array(0,1,42,42,43,42,42))" ) << QStringLiteral( "array_majority(array(0,1,42,42,43,42,42))" ) << false << QVariant( 42 );
-
       QTest::newRow( "array_minority('forty two')" ) << QStringLiteral( "array_minority('forty two')" ) << true << QVariant();
       QTest::newRow( "array_minority(42)" ) << QStringLiteral( "array_minority(42)" ) << true << QVariant();
       QTest::newRow( "array_minority(array())" ) << QStringLiteral( "array_minority(array())" ) << false << QVariant( QVariantList() );
-      QTest::newRow( "array_minority(array(42,43))" ) << QStringLiteral( "array_minority(array(42,43))" ) << false << QVariant( QVariantList() << 42 << 43 );
-      QTest::newRow( "array_minority(array(42,43,42))" ) << QStringLiteral( "array_minority(array(42,43,42))" ) << false << QVariant( QVariantList() << 43 );
-
+      QTest::newRow( "array_minority(array(1,42,43,42))" ) << QStringLiteral( "array_sort(array_minority(array(1,42,43,42)))" ) << false << QVariant( QVariantList() << 1 << 42 << 43 );
+      QTest::newRow( "array_minority(array(1,42,43,42,42))" ) << QStringLiteral( "array_sort(array_minority(array(1,42,43,42,42)))" ) << false << QVariant( QVariantList() << 1 << 43 );
       QTest::newRow( "array_sum('forty two')" ) << QStringLiteral( "array_sum('forty two')" ) << true << QVariant();
       QTest::newRow( "array_sum(42)" ) << QStringLiteral( "array_sum(42)" ) << true << QVariant();
       QTest::newRow( "array_sum(array())" ) << QStringLiteral( "array_sum(array())" ) << false << QVariant();