public void FindElements(XYExtent extent, List <T> elmts)
            {
                // If no overlap, just return
                if (!_extent.Overlaps(extent))
                {
                    return;
                }

                // If has children, ask those
                if (HasChildren)
                {
                    foreach (TreeNode child in _children)
                    {
                        child.FindElements(extent, elmts);
                    }
                }
                else // No children, search in elements of this node.
                {
                    foreach (Leaf <T> elmtLeaf in _elements)
                    {
                        if (elmtLeaf.Extent.Overlaps(extent))
                        {
                            // Check if it is already there
                            if (!elmts.Contains(elmtLeaf.Element))
                            {
                                elmts.Add(elmtLeaf.Element);
                            }
                        }
                    }
                }
            }
        /// <summary>
        /// Find elements with extends that overlaps the provided <paramref name="extent"/>
        /// </summary>
        /// <param name="extent">Extent to look for elements within</param>
        /// <returns>A list of elements with overlapping extents</returns>
        public ICollection <T> FindElements(XYExtent extent)
        {
            List <T> elmts = new List <T>();

            _head.FindElements(extent, elmts);
            return(elmts);
        }
Exemple #3
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 /// <summary>
 /// Checks if this extent overlaps the other extent
 /// </summary>
 /// <param name="other">Extent to check overlap with</param>
 /// <returns>True if the two extends overlaps</returns>
 public bool Overlaps(XYExtent other)
 {
     return
         (
         XMin <= other.XMax && XMax >= other.XMin &&
         YMin <= other.YMax && YMax >= other.YMin
         );
 }
        /// <summary>
        /// Add element to the search tree.
        /// </summary>
        /// <param name="element">Element to add</param>
        /// <param name="extent">Extent that contains the element</param>
        public void AddElement(T element, XYExtent extent)
        {
            Leaf <T> leaf = new Leaf <T>
            {
                Element = element,
                Extent  = extent,
            };

            _head.Add(leaf);
            _numElmts++;
        }
        /// <summary>
        /// Build a search tree based on an <see cref="IElementSet"/>, containing
        /// element index references.
        /// </summary>
        /// <param name="elmtSet">Element set to build search tree around</param>
        /// <returns>Search tree</returns>
        public static XYElementSearchTree <int> BuildSearchTree(IElementSet elmtSet)
        {
            // Calculate start extent
            XYExtent extent       = new XYExtent();
            int      elementCount = elmtSet.ElementCount;

            for (int ielmt = 0; ielmt < elementCount; ielmt++)
            {
                int vertixCount = elmtSet.GetVertexCount(ielmt);
                for (int ivert = 0; ivert < vertixCount; ivert++)
                {
                    double x = elmtSet.GetVertexXCoordinate(ielmt, ivert);
                    double y = elmtSet.GetVertexYCoordinate(ielmt, ivert);
                    extent.Include(x, y);
                }
            }
            // Create and build search tree, based on all vertex coordinates
            XYElementSearchTree <int> tree = new XYElementSearchTree <int>(extent);

            for (int ielmt = 0; ielmt < elementCount; ielmt++)
            {
                int vertixCount = elmtSet.GetVertexCount(ielmt);
                for (int ivert = 0; ivert < vertixCount; ivert++)
                {
                    double x = elmtSet.GetVertexXCoordinate(ielmt, ivert);
                    double y = elmtSet.GetVertexYCoordinate(ielmt, ivert);
                    tree.Add(new XYPoint(x, y));
                }
            }

            // Add elements to the search tree
            for (int ielmt = 0; ielmt < elementCount; ielmt++)
            {
                int      vertixCount = elmtSet.GetVertexCount(ielmt);
                XYExtent elmtExtent  = new XYExtent();
                for (int ivert = 0; ivert < vertixCount; ivert++)
                {
                    double x = elmtSet.GetVertexXCoordinate(ielmt, ivert);
                    double y = elmtSet.GetVertexYCoordinate(ielmt, ivert);
                    elmtExtent.Include(x, y);
                }
                tree.AddElement(ielmt, elmtExtent);
            }
            return(tree);
        }
Exemple #6
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 /// <summary>
 /// Make this extent include <paramref name="other"/>. This will
 /// grow this extent, if the <paramref name="other"/> point is outside
 /// this extent.
 /// </summary>
 /// <param name="other">Other extent to include</param>
 public void Include(XYExtent other)
 {
     if (other.XMin < XMin)
     {
         XMin = other.XMin;
     }
     if (other.XMax > XMax)
     {
         XMax = other.XMax;
     }
     if (other.YMin < YMin)
     {
         YMin = other.YMin;
     }
     if (other.YMax > YMax)
     {
         YMax = other.YMax;
     }
 }
Exemple #7
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        /// <summary>
        /// Calculates the mapping matrix between fromElements and toElements. The mapping method
        /// is decided from the combination of methodDescription, fromElements.ElementType and
        /// toElements.ElementType.
        /// The valid values for methodDescription is obtained through use of the
        /// GetAvailableMethods method.
        /// </summary>
        ///
        /// <remarks>
        /// UpdateMappingMatrix is called during initialisation. UpdateMappingMatrix must be called prior
        /// to Mapvalues.
        /// </remarks>
        ///
        /// <param name="methodIdentifier">String identification of mapping method</param>
        /// <param name="fromElements">The IElementset to map from.</param>
        /// <param name="toElements">The IElementset to map to</param>
        ///
        /// <returns>
        /// The method has no return value.
        /// </returns>
        private void UpdateMappingMatrix(ref IIdentifiable methodIdentifier, ref IElementSet fromElements, ref IElementSet toElements)
        {
            try
            {
                ElementSetChecker.CheckElementSet(fromElements);
                ElementSetChecker.CheckElementSet(toElements);

                _method              = SpatialAdaptedOutputFactory.GetMethod(methodIdentifier);
                _numberOfToRows      = toElements.ElementCount;
                _numberOfFromColumns = fromElements.ElementCount;
                _mappingMatrix       = new DoubleSparseMatrix(_numberOfToRows, _numberOfFromColumns);

                if (fromElements.ElementType == ElementType.Point && toElements.ElementType == ElementType.Point)
                {
                    #region

                    try
                    {
                        for (int i = 0; i < _numberOfToRows; i++)
                        {
                            XYPoint toPoint = CreateXYPoint(toElements, i);
                            for (int j = 0; j < _numberOfFromColumns; j++)
                            {
                                XYPoint fromPoint = CreateXYPoint(fromElements, j);
                                _mappingMatrix[i, j] = XYGeometryTools.CalculatePointToPointDistance(toPoint, fromPoint);
                            }
                        }

                        if (_method == ElementMapperMethod.Nearest)
                        {
                            for (int i = 0; i < _numberOfToRows; i++)
                            {
                                double minDist = _mappingMatrix[i, 0];
                                for (int j = 1; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] < minDist)
                                    {
                                        minDist = _mappingMatrix[i, j];
                                    }
                                }
                                int denominator = 0;
                                for (int j = 0; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] == minDist)
                                    {
                                        _mappingMatrix[i, j] = 1;
                                        denominator++;
                                    }
                                    else
                                    {
                                        _mappingMatrix[i, j] = 0;
                                    }
                                }
                                for (int j = 0; j < _numberOfFromColumns; j++)
                                {
                                    _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                }
                            }
                        }
                        else if (_method == ElementMapperMethod.Inverse)
                        {
                            for (int i = 0; i < _numberOfToRows; i++)
                            {
                                double minDist = _mappingMatrix[i, 0];
                                for (int j = 1; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] < minDist)
                                    {
                                        minDist = _mappingMatrix[i, j];
                                    }
                                }
                                if (minDist == 0)
                                {
                                    int denominator = 0;
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        if (_mappingMatrix[i, j] == minDist)
                                        {
                                            _mappingMatrix[i, j] = 1;
                                            denominator++;
                                        }
                                        else
                                        {
                                            _mappingMatrix[i, j] = 0;
                                        }
                                    }
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                    }
                                }
                                else
                                {
                                    double denominator = 0;
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = 1 / _mappingMatrix[i, j];
                                        denominator          = denominator + _mappingMatrix[i, j];
                                    }
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                    }
                                }
                            }
                        }
                        else
                        {
                            throw new Exception("methodDescription unknown for point point mapping");
                        }
                    }
                    catch (Exception e)
                    {
                        throw new Exception("Point to point mapping failed", e);
                    }

                    #endregion
                }
                else if (fromElements.ElementType == ElementType.Point && toElements.ElementType == ElementType.PolyLine)
                {
                    #region

                    try
                    {
                        for (int i = 0; i < _numberOfToRows; i++)
                        {
                            XYPolyline toPolyLine = CreateXYPolyline(toElements, i);
                            for (int j = 0; j < _numberOfFromColumns; j++)
                            {
                                XYPoint fromPoint = CreateXYPoint(fromElements, j);
                                _mappingMatrix[i, j] = XYGeometryTools.CalculatePolylineToPointDistance(toPolyLine,
                                                                                                        fromPoint);
                            }
                        }

                        if (_method == ElementMapperMethod.Nearest)
                        {
                            for (int i = 0; i < _numberOfToRows; i++)
                            {
                                double minDist = _mappingMatrix[i, 0];
                                for (int j = 1; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] < minDist)
                                    {
                                        minDist = _mappingMatrix[i, j];
                                    }
                                }
                                int denominator = 0;
                                for (int j = 0; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] == minDist)
                                    {
                                        _mappingMatrix[i, j] = 1;
                                        denominator++;
                                    }
                                    else
                                    {
                                        _mappingMatrix[i, j] = 0;
                                    }
                                }
                                for (int j = 0; j < _numberOfFromColumns; j++)
                                {
                                    _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                }
                            }
                        }
                        else if (_method == ElementMapperMethod.Inverse)
                        {
                            for (int i = 0; i < _numberOfToRows; i++)
                            {
                                double minDist = _mappingMatrix[i, 0];
                                for (int j = 1; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] < minDist)
                                    {
                                        minDist = _mappingMatrix[i, j];
                                    }
                                }
                                if (minDist == 0)
                                {
                                    int denominator = 0;
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        if (_mappingMatrix[i, j] == minDist)
                                        {
                                            _mappingMatrix[i, j] = 1;
                                            denominator++;
                                        }
                                        else
                                        {
                                            _mappingMatrix[i, j] = 0;
                                        }
                                    }
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                    }
                                }
                                else
                                {
                                    double denominator = 0;
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = 1 / _mappingMatrix[i, j];
                                        denominator          = denominator + _mappingMatrix[i, j];
                                    }
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                    }
                                }
                            }
                        }
                        else
                        {
                            throw new Exception("methodDescription unknown for point to polyline mapping");
                        }
                    }
                    catch (Exception e)
                    {
                        throw new Exception("Point to polyline mapping failed", e);
                    }

                    #endregion
                }
                else if (fromElements.ElementType == ElementType.Point &&
                         toElements.ElementType == ElementType.Polygon)
                {
                    #region

                    try
                    {
                        for (int i = 0; i < _numberOfToRows; i++)
                        {
                            XYPolygon polygon = CreateXYPolygon(toElements, i);
                            int       count   = 0;
                            XYPoint   point;
                            for (int n = 0; n < _numberOfFromColumns; n++)
                            {
                                point = CreateXYPoint(fromElements, n);
                                if (XYGeometryTools.IsPointInPolygon(point, polygon))
                                {
                                    if (_method == ElementMapperMethod.Mean)
                                    {
                                        count = count + 1;
                                    }
                                    else if (_method == ElementMapperMethod.Sum)
                                    {
                                        count = 1;
                                    }
                                    else
                                    {
                                        throw new Exception(
                                                  "methodDescription unknown for point to polygon mapping");
                                    }
                                }
                            }
                            for (int n = 0; n < _numberOfFromColumns; n++)
                            {
                                point = CreateXYPoint(fromElements, n);

                                if (XYGeometryTools.IsPointInPolygon(point, polygon))
                                {
                                    _mappingMatrix[i, n] = 1.0 / count;
                                }
                            }
                        }
                    }
                    catch (Exception e)
                    {
                        throw new Exception("Point to polygon mapping failed", e);
                    }

                    #endregion
                }
                else if (fromElements.ElementType == ElementType.PolyLine &&
                         toElements.ElementType == ElementType.Point)
                {
                    #region

                    try
                    {
                        for (int i = 0; i < _numberOfToRows; i++)
                        {
                            XYPoint toPoint = CreateXYPoint(toElements, i);
                            for (int j = 0; j < _numberOfFromColumns; j++)
                            {
                                XYPolyline fromPolyLine = CreateXYPolyline(fromElements, j);
                                _mappingMatrix[i, j] =
                                    XYGeometryTools.CalculatePolylineToPointDistance(fromPolyLine, toPoint);
                            }
                        }

                        if (_method == ElementMapperMethod.Nearest)
                        {
                            for (int i = 0; i < _numberOfToRows; i++)
                            {
                                double minDist = _mappingMatrix[i, 0];
                                for (int j = 1; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] < minDist)
                                    {
                                        minDist = _mappingMatrix[i, j];
                                    }
                                }
                                int denominator = 0;
                                for (int j = 0; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] == minDist)
                                    {
                                        _mappingMatrix[i, j] = 1;
                                        denominator++;
                                    }
                                    else
                                    {
                                        _mappingMatrix[i, j] = 0;
                                    }
                                }
                                for (int j = 0; j < _numberOfFromColumns; j++)
                                {
                                    _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                }
                            }
                        }
                        else if (_method == ElementMapperMethod.Inverse)
                        {
                            for (int i = 0; i < _numberOfToRows; i++)
                            {
                                double minDist = _mappingMatrix[i, 0];
                                for (int j = 1; j < _numberOfFromColumns; j++)
                                {
                                    if (_mappingMatrix[i, j] < minDist)
                                    {
                                        minDist = _mappingMatrix[i, j];
                                    }
                                }
                                if (minDist == 0)
                                {
                                    int denominator = 0;
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        if (_mappingMatrix[i, j] == minDist)
                                        {
                                            _mappingMatrix[i, j] = 1;
                                            denominator++;
                                        }
                                        else
                                        {
                                            _mappingMatrix[i, j] = 0;
                                        }
                                    }
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                    }
                                }
                                else
                                {
                                    double denominator = 0;
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = 1 / _mappingMatrix[i, j];
                                        denominator          = denominator + _mappingMatrix[i, j];
                                    }
                                    for (int j = 0; j < _numberOfFromColumns; j++)
                                    {
                                        _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                    }
                                }
                            }
                        }
                        else
                        {
                            throw new Exception("methodDescription unknown for polyline to point mapping");
                        }
                    }
                    catch (Exception e) // Catch for all of the Point to Polyline part
                    {
                        throw new Exception("Polyline to point mapping failed", e);
                    }

                    #endregion
                }
                else if (fromElements.ElementType == ElementType.PolyLine &&
                         toElements.ElementType == ElementType.Polygon)
                {
                    #region

                    try
                    {
                        // For each polygon in target
                        for (int i = 0; i < _numberOfToRows; i++)
                        {
                            XYPolygon polygon = CreateXYPolygon(toElements, i);

                            if (_method == ElementMapperMethod.WeightedMean)
                            {
                                double totalLineLengthInPolygon = 0;
                                for (int n = 0; n < _numberOfFromColumns; n++)
                                {
                                    XYPolyline polyline = CreateXYPolyline(fromElements, n);
                                    _mappingMatrix[i, n] =
                                        XYGeometryTools.CalculateLengthOfPolylineInsidePolygon(
                                            polyline, polygon);
                                    totalLineLengthInPolygon += _mappingMatrix[i, n];
                                }
                                if (totalLineLengthInPolygon > 0)
                                {
                                    for (int n = 0; n < _numberOfFromColumns; n++)
                                    {
                                        _mappingMatrix[i, n] = _mappingMatrix[i, n] /
                                                               totalLineLengthInPolygon;
                                    }
                                }
                            }
                            else if (_method == ElementMapperMethod.WeightedSum)
                            {
                                // For each line segment in PolyLine
                                for (int n = 0; n < _numberOfFromColumns; n++)
                                {
                                    XYPolyline polyline = CreateXYPolyline(fromElements, n);
                                    _mappingMatrix[i, n] =
                                        XYGeometryTools.CalculateLengthOfPolylineInsidePolygon(
                                            polyline, polygon) / polyline.GetLength();
                                }
                            }
                            else
                            {
                                throw new Exception(
                                          "methodDescription unknown for polyline to polygon mapping");
                            }
                        }
                    }
                    catch (Exception e)
                    {
                        throw new Exception("Polyline to polygon mapping failed", e);
                    }

                    #endregion
                }
                else if (fromElements.ElementType == ElementType.Polygon &&
                         toElements.ElementType == ElementType.Point)
                {
                    #region

                    try
                    {
                        if (_method != ElementMapperMethod.Value)
                        {
                            throw new Exception("methodDescription unknown for polygon to point mapping");
                        }

                        // Only create search tree if number of cols/rows is larger than say 10/10.
                        bool useSearchTree = _numberOfFromColumns > 10 && _numberOfToRows > 10;
                        XYElementSearchTree <int> fromSearchTree     = null;
                        ICollection <int>         fromCandidateElmts = null;
                        if (useSearchTree)
                        {
                            fromSearchTree = XYElementSearchTree <int> .BuildSearchTree(fromElements);
                        }
                        else
                        {
                            fromCandidateElmts = new IntSequence(0, _numberOfFromColumns - 1);
                        }

                        for (int n = 0; n < _numberOfToRows; n++)
                        {
                            XYPoint point = CreateXYPoint(toElements, n);
                            if (useSearchTree)
                            {
                                XYExtent toExtent = XYExtentUtil.GetExtent(point, XYGeometryTools.EPSILON);
                                fromCandidateElmts = fromSearchTree.FindElements(toExtent);
                            }

                            int count = 0;

                            // Check first for strict inclusion
                            foreach (int i in fromCandidateElmts)
                            {
                                XYPolygon polygon = CreateXYPolygon(fromElements, i);
                                if (XYGeometryTools.IsPointInPolygon(point, polygon))
                                {
                                    _mappingMatrix[n, i] = 1.0;
                                    count++;
                                }
                            }
                            if (count == 0)
                            {
                                // Not strictly inside any polygon, check also edges
                                foreach (int i in fromCandidateElmts)
                                {
                                    XYPolygon polygon = CreateXYPolygon(fromElements, i);
                                    if (XYGeometryTools.IsPointInPolygonOrOnEdge(point, polygon))
                                    {
                                        _mappingMatrix[n, i] = 1.0;
                                        count++;
                                    }
                                }
                            }
                            if (count > 1)
                            {
                                // In case of more than one hit, use average
                                foreach (int i in fromCandidateElmts)
                                {
                                    if (_mappingMatrix[n, i] != 0.0)
                                    {
                                        _mappingMatrix[n, i] = 1.0 / count;
                                    }
                                }
                            }
                        }
                    }
                    catch (Exception e)
                    {
                        throw new Exception("Polygon to point mapping failed", e);
                    }

                    #endregion
                }
                else if (fromElements.ElementType == ElementType.Polygon &&
                         toElements.ElementType == ElementType.PolyLine)
                // Polygon to PolyLine
                {
                    #region

                    try
                    {
                        for (int i = 0; i < _numberOfToRows; i++)
                        {
                            XYPolyline polyline = CreateXYPolyline(toElements, i);

                            if (_method == ElementMapperMethod.WeightedMean)
                            {
                                for (int n = 0; n < _numberOfFromColumns; n++)
                                {
                                    XYPolygon polygon = CreateXYPolygon(fromElements, n);
                                    _mappingMatrix[i, n] =
                                        XYGeometryTools.CalculateLengthOfPolylineInsidePolygon(
                                            polyline, polygon) / polyline.GetLength();
                                }
                                double sum = 0;
                                for (int n = 0; n < _numberOfFromColumns; n++)
                                {
                                    sum += _mappingMatrix[i, n];
                                }
                                for (int n = 0; n < _numberOfFromColumns; n++)
                                {
                                    _mappingMatrix[i, n] = _mappingMatrix[i, n] / sum;
                                }
                            }
                            else if (_method == ElementMapperMethod.WeightedSum)
                            {
                                for (int n = 0; n < _numberOfFromColumns; n++)
                                {
                                    XYPolygon polygon = CreateXYPolygon(fromElements, n);
                                    _mappingMatrix[i, n] =
                                        XYGeometryTools.CalculateLengthOfPolylineInsidePolygon(
                                            polyline, polygon) / polyline.GetLength();
                                }
                            }
                            else
                            {
                                throw new Exception(
                                          "methodDescription unknown for polygon to polyline mapping");
                            }
                        }
                    }
                    catch (Exception e) // catch for all of Polygon to PolyLine
                    {
                        throw new Exception("Polygon to polyline mapping failed", e);
                    }

                    #endregion
                }
                else if (fromElements.ElementType == ElementType.Polygon &&
                         toElements.ElementType == ElementType.Polygon)
                // Polygon to Polygon
                {
                    #region

                    try
                    {
                        // Only create search tree if number of cols/rows is larger than say 100/10.
                        bool useSearchTree = _numberOfFromColumns > 10 && _numberOfToRows > 10;
                        XYElementSearchTree <int> fromSearchTree     = null;
                        ICollection <int>         fromCandidateElmts = null;
                        if (useSearchTree)
                        {
                            fromSearchTree = XYElementSearchTree <int> .BuildSearchTree(fromElements);
                        }
                        else
                        {
                            fromCandidateElmts = new IntSequence(0, _numberOfFromColumns - 1);
                        }

                        for (int i = 0; i < _numberOfToRows; i++)
                        {
                            XYPolygon toPolygon = CreateXYPolygon(toElements, i);
                            if (useSearchTree)
                            {
                                XYExtent toExtent = XYExtentUtil.GetExtent(toPolygon);
                                fromCandidateElmts = fromSearchTree.FindElements(toExtent);
                            }

                            foreach (int j in fromCandidateElmts)
                            {
                                XYPolygon fromPolygon = CreateXYPolygon(fromElements, j);
                                _mappingMatrix[i, j] = XYGeometryTools.CalculateSharedArea(
                                    toPolygon, fromPolygon);
                                if (_method == ElementMapperMethod.Distribute)
                                {
                                    _mappingMatrix[i, j] /= fromPolygon.GetArea();
                                }
                            }

                            if (_method == ElementMapperMethod.WeightedMean)
                            {
                                double denominator = 0;
                                foreach (int j in fromCandidateElmts)
                                {
                                    denominator = denominator + _mappingMatrix[i, j];
                                }
                                foreach (int j in fromCandidateElmts)
                                {
                                    if (denominator != 0)
                                    {
                                        _mappingMatrix[i, j] = _mappingMatrix[i, j] / denominator;
                                    }
                                }
                            }
                            else if (_method == ElementMapperMethod.WeightedSum)
                            {
                                foreach (int j in fromCandidateElmts)
                                {
                                    _mappingMatrix[i, j] = _mappingMatrix[i, j] / toPolygon.GetArea();
                                }
                            }
                            else if (_method != ElementMapperMethod.Distribute)
                            {
                                throw new Exception(
                                          "methodDescription unknown for polygon to polygon mapping");
                            }
                        }
                    }
                    catch (Exception e) // catch for all of Polygon to Polygon
                    {
                        throw new Exception("Polygon to polygon mapping failed", e);
                    }

                    #endregion
                }
                else // if the fromElementType, toElementType combination is no implemented
                {
                    throw new Exception(
                              "Mapping of specified ElementTypes not included in ElementMapper");
                }
            }
            catch (Exception e)
            {
                throw new Exception("UpdateMappingMatrix failed to update mapping matrix", e);
            }
        }
 /// <summary>
 /// Create a new search tree that covers the provided <paramref name="extent"/>
 /// </summary>
 /// <param name="extent">Extent that the search tree should cover</param>
 public XYElementSearchTree(XYExtent extent)
 {
     _head = new TreeNode(extent);
 }
 public TreeNode(XYExtent extent)
 {
     _extent = extent;
 }