Ejemplo n.º 1
0
        /// <summary>
        /// Evaluates the <see cref="SpatialDimension"/>-dimensional
        /// coordinate of the point with parameter value t.
        /// </summary>
        /// <param name="t"></param>
        /// <returns></returns>
        public double[] GetPointOnSegment(double t)
        {
            Debug.Assert(
                t.Abs() <= 1.0,
                "Point out of range");

            double[] result = new double[SpatialDimension];
            for (int d = 0; d < SpatialDimension; d++)
            {
                result[d] = 0.5 * ((End[d] - Start[d]) * t + Start[d] + End[d]);
            }
            return(result);
        }
Ejemplo n.º 2
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        private static IEnumerable <GradientStop> ScaleGradientStops(IEnumerable <GradientStop> gradientStops, Point startPoint, Point endPoint, Size targetSize)
        {
            if (startPoint.X == endPoint.X)
            {
                return(startPoint.Y < endPoint.Y ?
                       ScaleGradientStops(gradientStops, startPoint.Y / targetSize.Height, endPoint.Y / targetSize.Height) :
                       ScaleGradientStops(gradientStops, 1 - startPoint.Y / targetSize.Height, 1 - endPoint.Y / targetSize.Height));
            }

            if (startPoint.Y == endPoint.Y)
            {
                return(startPoint.X < endPoint.X ?
                       ScaleGradientStops(gradientStops, startPoint.X / targetSize.Width, endPoint.X / targetSize.Width) :
                       ScaleGradientStops(gradientStops, 1 - startPoint.X / targetSize.Width, 1 - endPoint.X / targetSize.Width));
            }

            Point  direction       = endPoint - startPoint;
            double directionLength = direction.GetLength();

            double sin = direction.Y / directionLength;
            double cos = direction.X / directionLength;

            // generated gradient image size
            double generatedImageWidth  = cos.Abs() * targetSize.Width + sin.Abs() * targetSize.Height;
            double generatedImageHeight = sin.Abs() * targetSize.Width + cos.Abs() * targetSize.Height;

            // transformation from a unit square to the generated gradient image rectangle
            Matrix matrix =
                Matrix.TranslationMatrix(-0.5, -0.5) *                                 // translate the unit square center to the origin
                Matrix.ScalingMatrix(generatedImageWidth, generatedImageHeight) *      // scale to the generated gradient image size
                new Matrix(cos, sin, -sin, cos, 0, 0) *                                // rotate to the generated gradient image angle
                Matrix.TranslationMatrix(targetSize.Width / 2, targetSize.Height / 2); // translate to the target rectangle center

            Point relativeStart = startPoint * matrix.Inverse;
            Point relativeEnd   = endPoint * matrix.Inverse;

            return(ScaleGradientStops(gradientStops, relativeStart.X, relativeEnd.X));
        }
Ejemplo n.º 3
0
        private bool Animate(double targetValue)
        {
            double diff = targetValue - percentOffset;

            if (diff.Abs() > MinimalValueDelta ||
                velocity.Abs() > MinimalVelocityDelta)
            {
                velocity  = velocity * (1 - Dampening);
                velocity += diff * AttractionFator;
                if (velocity.Abs() > TerminalVelocity)
                {
                    velocity *= TerminalVelocity / velocity.Abs();
                }

                percentOffset = percentOffset + velocity;

                return(true);
            }

            percentOffset = targetValue;
            velocity      = 0;
            return(false);
        }
        public static void ScaleFromPoint_Scales_Shape(double scale,
                                                       double expectedCentroid_x, double expectedCentroid_y)
        {
            List <CartesianCoordinate> bowTieNonCrossingSegmentsScaled = new List <CartesianCoordinate>()
            {
                new CartesianCoordinate(4, 3.5),
                new CartesianCoordinate(3, 5),
                new CartesianCoordinate(3, 2),
                new CartesianCoordinate(4, 3.5),
                new CartesianCoordinate(5, 2),
                new CartesianCoordinate(5, 5),
                new CartesianCoordinate(4, 3.5),
            };

            Polygon polygon = new Polygon(bowTieNonCrossingSegmentsScaled);

            // Check shape position
            CartesianCoordinate originalCentroid = polygon.Centroid;

            Assert.AreEqual(4, originalCentroid.X);
            Assert.AreEqual(3.5, originalCentroid.Y);

            CartesianCoordinate referencePoint = new CartesianCoordinate(2, 1);
            Polygon             polygonScaled  = polygon.ScaleFromPoint(scale, referencePoint) as Polygon;

            // Check shape scale
            PointExtents extents = polygonScaled.Extents();

            Assert.AreEqual(2 * scale.Abs(), extents.Width);
            Assert.AreEqual(3 * scale.Abs(), extents.Height);

            // Check scaled centroid position
            CartesianCoordinate scaledCentroid = polygonScaled.Centroid;

            Assert.AreEqual(expectedCentroid_x, scaledCentroid.X);
            Assert.AreEqual(expectedCentroid_y, scaledCentroid.Y);
        }
Ejemplo n.º 5
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        private void GetCornerD(DragDeltaEventArgs e, out double dx, out double dy, double invert)
        {
            var multiplier = GetScaleMultiplier();

            dx = e.HorizontalChange * Viewbox.Scale.Width * multiplier;
            dy = e.VerticalChange * Viewbox.Scale.Height * multiplier;
            if (dx.Abs() > dy.Abs())
            {
                dx = invert.Sign() * dy * _model.TargetWidth / _model.TargetHeight;
            }
            else
            {
                dy = invert.Sign() * dx * _model.TargetHeight / _model.TargetWidth;
            }
        }
Ejemplo n.º 6
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        // Reset this spring to its initial state
        public void Reset()
        {
            double mass = 0;

            if (Element?.Geometry != null)
            {
                if (Element.Family != null)
                {
                    Stiffness = Element.Family.GetAxialStiffness();
                    mass      = Element.Family.GetArea();
                    mass     *= Element.Family.GetPrimaryMaterial()?.Density ?? 0;
                }
                else
                {
                    Stiffness = 0;
                }
            }
            if (Element.StartNode != null)
            {
                StartParticle = Element.StartNode.GetData <Particle>();
            }
            if (Element.EndNode != null)
            {
                EndParticle = Element.EndNode.GetData <Particle>();
            }
            RestLength = Element.EndNode.Position.DistanceTo(Element.StartNode.Position);
            mass      *= RestLength;

            // Lump stiffness at nodes:
            Vector dir    = EndParticle.Position - StartParticle.Position;
            double length = dir.Magnitude();

            dir /= length;
            double extension = length - RestLength;
            double T         = extension * Stiffness;
            double Ke        = Stiffness / RestLength;
            double Kg        = T.Abs() / length;
            double K         = 0.5 * (Ke + Kg);
            Vector Kv        = dir.Abs() * K;

            // Hmmm... do we need to worry about signs?
            StartParticle.LumpedK += Kv;
            EndParticle.LumpedK   += Kv;

            // Lump mass at nodes:
            StartParticle.Mass += mass / 2;
            EndParticle.Mass   += mass / 2;
        }
Ejemplo n.º 7
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        private static void GetPoints(double angle, out Point startPoint, out Point endPoint)
        {
            double radians = Math.PI * angle / 180;
            double x       = Math.Cos(radians);
            double y       = Math.Sin(radians);

            double scale = 1 / x.Abs().Max(y.Abs());

            x *= scale;
            y *= scale;

            Point offset = new Point(x.Min(0), y.Min(0));

            startPoint = -offset;
            endPoint   = new Point(x, y) - offset;
        }
Ejemplo n.º 8
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        public bool Animate(
            double currentValue, double currentVelocity, double targetValue,
            double attractionFator, double dampening,
            double terminalVelocity, double minValueDelta, double minVelocityDelta,
            out double newValue, out double newVelocity)
        {
            Debug.Assert(currentValue.IsValid());
            Debug.Assert(currentVelocity.IsValid());
            Debug.Assert(targetValue.IsValid());

            Debug.Assert(dampening.IsValid());
            Debug.Assert(dampening > 0 && dampening < 1);

            Debug.Assert(attractionFator.IsValid());
            Debug.Assert(attractionFator > 0);

            Debug.Assert(terminalVelocity > 0);

            Debug.Assert(minValueDelta > 0);
            Debug.Assert(minVelocityDelta > 0);

            double diff = targetValue - currentValue;

            if (diff.Abs() > minValueDelta || currentVelocity.Abs() > minVelocityDelta)
            {
                newVelocity  = currentVelocity * (1 - dampening);
                newVelocity += diff * attractionFator;
                if (currentVelocity.Abs() > terminalVelocity)
                {
                    newVelocity *= terminalVelocity / currentVelocity.Abs();
                }

                newValue = currentValue + newVelocity;

                return(true);
            }
            else
            {
                newValue    = targetValue;
                newVelocity = 0;
                return(false);
            }
        }
Ejemplo n.º 9
0
        /// <summary>
        ///
        /// </summary>
        /// <param name="Lab"></param>
        /// <param name="Observer"></param>
        /// <param name="Illuminant"></param>
        public Lch(Lab Lab, ObserverAngle Observer = ObserverAngle.Two, Illuminant Illuminant = Illuminant.Default) : this(0, 0, 0, Observer, Illuminant)
        {
            double l, c, h = Math.Atan2(Lab.B, Lab.A);

            if (h > 0d)
            {
                h = (h / Math.PI) * 180d;
            }
            else
            {
                h = 360d - (h.Abs() / Math.PI) * 180d;
            }

            l = Lab.L;
            c = Math.Sqrt(Math.Pow(Lab.A, 2d) + Math.Pow(Lab.B, 2d));

            L = l;
            C = c;
            H = h;
        }
Ejemplo n.º 10
0
        private Pen GetPen()
        {
            double strokeThickness = StrokeThickness;

            if (Stroke == null ||
                strokeThickness.IsNaNValue() ||
                strokeThickness.IsEqualOrCloseToZero())
            {
                return(null);
            }

            if (strokePen != null)
            {
                return(strokePen);
            }

            double thickness = strokeThickness.Abs();

            strokePen = new Pen
            {
                Thickness    = thickness,
                Brush        = Stroke,
                StartLineCap = StrokeStartLineCap,
                EndLineCap   = StrokeEndLineCap,
                DashCap      = StrokeDashCap,
                LineJoin     = StrokeLineJoin,
                MiterLimit   = StrokeMiterLimit
            };

            if (StrokeDashArray != null ||
                !StrokeDashOffset.IsEqualOrCloseToZero())
            {
                strokePen.DashStyle = new DashStyle(StrokeDashArray, StrokeDashOffset);
            }

            strokePen.Freeze();
            return(strokePen);
        }
Ejemplo n.º 11
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        static double DistanceByHeightAndAngle(double heigth, double angle)
        {
            var a = angle.Abs();

            return(a >= 90 ? heigth * a / 90 : heigth / Math.Sin(a.Radians()));
        }
Ejemplo n.º 12
0
        public static double AutoRound2(this double d, int digits)
        {
            var digitsReal = Math.Log10(d.Abs()).Floor() + 1;

            return(d.Round((digits - digitsReal).Max(0)));
        }
Ejemplo n.º 13
0
 static bool IsTresholdAbsOk(double value, double treshold)
 {
     return(treshold >= 0 ? value.Abs() >= treshold : value.Abs() < -treshold);
 }
Ejemplo n.º 14
0
        /// <summary>
        /// Usually used after <see cref="MergeLogically(GridCommons, GridCommons)"/>; this method finds element boundaries
        /// which intersect geometrically, but not logically and inserts a <see cref="CellFaceTag"/> which connects those cells.
        /// </summary>
        /// <param name="g"></param>
        /// <param name="upsampling"></param>
        /// <returns></returns>
        public static GridCommons Seal(GridCommons g, int upsampling = 4)
        {
            GridCommons R = g.CloneAs();

            g = null;
            GridData gdat = new GridData(R);
            int      D    = gdat.SpatialDimension;
            int      J    = gdat.Cells.NoOfLocalUpdatedCells;

            if (R.CellPartitioning.MpiSize > 1)
            {
                throw new NotSupportedException("Not supported in MPI-parallel mode.");
            }

            //NodeSet[] TestNodes = gdat.Edges.EdgeRefElements.Select(KrefEdge => KrefEdge.GetSubdivisionTree(upsampling).GlobalVertice).ToArray();
            NodeSet[] TestNodes = gdat.Edges.EdgeRefElements.Select(KrefEdge => KrefEdge.GetBruteForceQuadRule(upsampling, 1).Nodes).ToArray();
            // Its better to use vertices in the interior of the element; if we use vertices at the corners, we might get
            // intersection of edges that just share one point.


            // Define all edges that will be tested (set to boundary edges)
            // ============================================================
            int[] UnknownEdges = gdat.BoundaryEdges.ItemEnum.ToArray();
            int   L            = UnknownEdges.Sum(iEdg => TestNodes[gdat.Edges.GetRefElementIndex(iEdg)].NoOfNodes);

            // Transform nodes on edges (that should be tested) to global coordinates
            // ======================================================================

            MultidimensionalArray TestNodesGlobal = MultidimensionalArray.Create(L, D);
            MultidimensionalArray NormalsGlobal   = MultidimensionalArray.Create(L, D);

            int[] NodeToEdge = new int[L]; // pointer l -> Edge index, where l is the first index into 'TestNodesGlobal' & 'NormalsGlobal'


            int[,] E2C = gdat.Edges.CellIndices;
            int cnt = 0;

            foreach (int iEdg in UnknownEdges)
            {
                int     iKref = gdat.Edges.GetRefElementIndex(iEdg);
                NodeSet Ns    = TestNodes[iKref];
                int     K     = Ns.NoOfNodes;

                int[] I0 = new int[] { cnt, 0 };
                int[] IE = new int[] { cnt + K - 1, D - 1 };

                MultidimensionalArray TN = gdat.GlobalNodes.GetValue_EdgeSV(Ns, iEdg, 1);
                TestNodesGlobal.SetSubArray(TN.ExtractSubArrayShallow(0, -1, -1), I0, IE);

                MultidimensionalArray N1 = gdat.Edges.NormalsCache.GetNormals_Edge(Ns, iEdg, 1);
                NormalsGlobal.SetSubArray(N1.ExtractSubArrayShallow(0, -1, -1), I0, IE);

                for (int i = cnt; i < cnt + K; i++)
                {
                    NodeToEdge[i] = iEdg;
                }

                cnt += K;
            }

            // binary tree to speed up point localization
            int[]             pl_Permutation = new int[L];
            PointLocalization pl             = new PointLocalization(TestNodesGlobal, 0.01, pl_Permutation);

            Debug.Assert(!object.ReferenceEquals(pl.Points, TestNodesGlobal));

            // compare search edges to all other nodes
            // =======================================

            // mapping: cell --> Neighbour cell index, face index
            // 1st index: Cell index;
            // 2nd index: enumeration
            List <Tuple <int, int> >[] FoundPairings = new List <Tuple <int, int> > [gdat.Cells.NoOfCells];

            int[][] C2E = gdat.Cells.Cells2Edges;
            byte[,] E2F = gdat.Edges.FaceIndices;

            int cnt2 = 0;

            for (int iEdgC = 0; iEdgC < UnknownEdges.Length; iEdgC++)   // loop over edges that may get sealed
            {
                int     iEdg  = UnknownEdges[iEdgC];
                int     iKref = gdat.Edges.GetRefElementIndex(iEdg);
                NodeSet Ns    = TestNodes[iKref];
                int     K     = Ns.NoOfNodes;

                int jCell1 = E2C[iEdg, 0];
                Debug.Assert(E2C[iEdg, 1] < 0);
                int iFace1 = E2F[iEdg, 0];
                Debug.Assert(E2F[iEdg, 1] == byte.MaxValue);


                int[] I0 = new int[] { cnt2, 0 };
                int[] IE = new int[] { cnt2 + K - 1, D - 1 };
                MultidimensionalArray TN = TestNodesGlobal.ExtractSubArrayShallow(I0, IE);
                //MultidimensionalArray N1 = NormalsGlobal.ExtractSubArrayShallow(I0, IE);

                // find bounding box for edge
                BoundingBox bbEdge = new BoundingBox(TN);
                if (bbEdge.h_min / bbEdge.h_max < 1.0e-5)
                {
                    // very thin bounding box, thicken slightly
                    double delta = bbEdge.h_max * 1.0e-5;
                    for (int d = 0; d < D; d++)
                    {
                        bbEdge.Min[d] -= delta;
                        bbEdge.Max[d] += delta;
                    }
                }
                bbEdge.ExtendByFactor(0.01);

                // determine binary code for bounding box
                int bbEdgeSigBits;
                GeomBinTreeBranchCode bbEdgeCode = GeomBinTreeBranchCode.Combine(
                    GeomBinTreeBranchCode.CreateFormPoint(pl.PointsBB, bbEdge.Min),
                    GeomBinTreeBranchCode.CreateFormPoint(pl.PointsBB, bbEdge.Max),
                    out bbEdgeSigBits);

                // determine all points in bounding box
                int iP0, Len;
                pl.GetPointsInBranch(bbEdgeCode, bbEdgeSigBits, out iP0, out Len);

                // determine all edged which potentially overlap with edge 'iEdg'
                HashSet <int> PotOvrlap = new HashSet <int>(); // a set of edge indices
                for (int n = 0; n < Len; n++)
                {
                    int l   = iP0 + n;
                    int iPt = pl_Permutation[l];
                    Debug.Assert(GenericBlas.L2DistPow2(pl.Points.GetRow(l), TestNodesGlobal.GetRow(iPt)) <= 0);

                    int iOvlpEdge = NodeToEdge[iPt];
                    if (iOvlpEdge != iEdg)
                    {
                        PotOvrlap.Add(iOvlpEdge);
                    }
                }
                //int[] PotOvrlap = UnknownEdges.CloneAs();


                // determine actually overlapping boundary edges:
                foreach (int iOvrlapEdge in PotOvrlap)
                {
                    int jCell2 = E2C[iOvrlapEdge, 0];
                    Debug.Assert(E2C[iOvrlapEdge, 1] < 0);
                    if (jCell2 == jCell1)
                    {
                        continue;
                    }
                    int iFace2 = E2F[iOvrlapEdge, 0];
                    Debug.Assert(E2F[iOvrlapEdge, 1] == byte.MaxValue);


                    int AllreadyFound = FoundPairings[jCell1] == null ?
                                        0 : FoundPairings[jCell1].Where(tp => tp.Item1 == jCell2 && tp.Item2 == iFace1).Count();
                    if (AllreadyFound > 1)
                    {
                        throw new ApplicationException("Error in algorithmus.");
                    }
                    if (AllreadyFound > 0)
                    {
                        continue;
                    }

                    var    Kref_j2 = gdat.Cells.GetRefElement(jCell2);
                    double h       = Kref_j2.GetMaxDiameter();

                    MultidimensionalArray LocVtx_j2 = MultidimensionalArray.Create(K, D);
                    bool[] NewtonConvervence        = new bool[K];
                    gdat.TransformGlobal2Local(TN, LocVtx_j2, jCell2, NewtonConvervence);

                    for (int k = 0; k < K; k++)   // loop over all transformed points
                    {
                        if (!NewtonConvervence[k])
                        {
                            continue;
                        }

                        double[] pt      = LocVtx_j2.GetRow(k);
                        double[] ptClose = new double[D];
                        double   dist    = Kref_j2.ClosestPoint(pt, ptClose);

                        if (dist > h * 1.0e-8)
                        {
                            continue;
                        }

                        AffineManifold Face     = Kref_j2.GetFacePlane(iFace2);
                        double         FaceDist = Face.PointDistance(pt);

                        if (FaceDist.Abs() > 1.0e-8 * h)
                        {
                            continue;
                        }


                        NodeSet Ns2 = new NodeSet(Kref_j2, pt);
                        MultidimensionalArray Normals2 = MultidimensionalArray.Create(1, D);
                        gdat.Edges.GetNormalsForCell(Ns2, jCell2, iFace2, Normals2);

                        double[] N1d = NormalsGlobal.GetRow(cnt2 + k);
                        double[] N2d = Normals2.GetRow(0);


                        //Check if face normals points exactly in the opposite direction, 2 ways:
                        // 1) calculate angle between both normals -> bad choice because of Math.Acos
                        // 2) inner product of two opposite vectors is -1
                        //if (Math.Abs(Math.Abs(Math.Acos(GenericBlas.InnerProd(N1d, N2d))) - Math.PI) > 1.0e-8)
                        if (Math.Abs(GenericBlas.InnerProd(N1d, N2d) + 1.0) > 1.0e-8)
                        {
                            continue;
                        }



                        // if we reach this point, jCell1 should match with jCell2/iFace2
                        if (FoundPairings[jCell1] == null)
                        {
                            FoundPairings[jCell1] = new List <Tuple <int, int> >();
                        }
                        if (FoundPairings[jCell2] == null)
                        {
                            FoundPairings[jCell2] = new List <Tuple <int, int> >();
                        }
                        FoundPairings[jCell1].Add(new Tuple <int, int>(jCell2, iFace1));
                        FoundPairings[jCell2].Add(new Tuple <int, int>(jCell1, iFace2));
                        break; // no need to test jCell1 vs. jCell2 anymore
                    }
                }

                cnt2 += K;
            }

            // add the newly found pairings to the grid
            for (int j = 0; j < J; j++)
            {
                var fp = FoundPairings[j];
                if (fp != null)
                {
                    foreach (var t in fp)
                    {
                        ArrayTools.AddToArray(new CellFaceTag()
                        {
                            EdgeTag               = 0,
                            FaceIndex             = t.Item2,
                            ConformalNeighborship = false,
                            NeighCell_GlobalID    = gdat.CurrentGlobalIdPermutation.Values[t.Item1]
                        }, ref R.Cells[j].CellFaceTags);
                    }
                }
            }

            return(R);
        }
Ejemplo n.º 15
0
 public void DoAbs(double value, double expectedValue)
 {
     Assert.Equal(expectedValue, value.Abs());
 }
Ejemplo n.º 16
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        public static int IteratonSequenceNextStep(int count, double power = 1, int loop = 0)
        {
            var p = count / 100.0 * Math.Pow(count, power.Abs()) / Math.Pow(2, loop.Abs());

            return(p.Ceiling() * power.Sign() * ((double)loop).SignUp());
        }
Ejemplo n.º 17
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 public static double Abs_Double(double value)
 {
     return(value.Abs());
 }
Ejemplo n.º 18
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        public bool LocalSolve(int jCell, BitArray AcceptedMask, SinglePhaseField Phi, double _sign, out double Min, out double Max)
        {
            Debug.Assert(_sign.Abs() == 1);


            // find all accepted neighbors
            // ===========================

            var NeighCells = this.GridDat.GetCellNeighboursViaEdges(jCell);
            int iKref      = this.GridDat.Cells.GetRefElementIndex(jCell);

            int NN          = NeighCells.Length;
            var NeighCellsK = new Tuple <int, int, int> [NN];
            int NNK         = 0;

            for (int nn = 0; nn < NN; nn++)
            {
                if (AcceptedMask[NeighCells[nn].Item1] == true)
                {
                    NeighCellsK[NNK] = NeighCells[nn];
                    NNK++;
                }
            }

            // evaluate accepted neighbors
            // ============================

            Min = double.MaxValue;
            Max = double.MinValue;

            var TrafoIdx = this.GridDat.Edges.Edge2CellTrafoIndex;
            int K        = this.PhiEvalBuffer[0].GetLength(1); // Nodes per edge

            for (int nnk = 0; nnk < NNK; nnk++)                // loop over accepted neighbours
            {
                int jNC     = NeighCellsK[nnk].Item1;
                int iEdg    = NeighCellsK[nnk].Item2;
                int InOrOut = NeighCellsK[nnk].Item3;
                int iTrafo  = TrafoIdx[iEdg, InOrOut];

                this.PhiEvalBuffer[nnk].Clear();
                Phi.Evaluate(jNC, 1, this.EdgeNodes.GetVolumeNodeSet(this.GridDat, iTrafo), this.PhiEvalBuffer[nnk]);

                this.GridDat.TransformLocal2Global(this.EdgeNodes.GetVolumeNodeSet(this.GridDat, iTrafo), this.CellNodesGlobal[nnk], jNC);

                Max = Math.Max(Max, PhiEvalBuffer[nnk].Max());
                Min = Math.Min(Min, PhiEvalBuffer[nnk].Min());
            }

            var _QuadNodesGlobal = this.QuadNodesGlobal[iKref];

            this.GridDat.TransformLocal2Global(this.DaRuleS[iKref].Nodes, _QuadNodesGlobal, jCell);

            if (_sign > 0)
            {
                Max += this.GridDat.Cells.h_max[jCell];
            }
            else
            {
                Min -= this.GridDat.Cells.h_max[jCell];
            }


            // perform projection of geometric reinit
            // ======================================

            // temp storage
            double[] Y  = new double[2];
            double[] X  = new double[2];
            double[] X1 = new double[2];
            double[] X2 = new double[2];

            // basis values at cell quadrature nodes
            var BasisValues = this.LevelSetBasis_Geometric.CellEval(this.DaRuleS[iKref].Nodes, jCell, 1).ExtractSubArrayShallow(0, -1, -1);
            int NoOfQn      = BasisValues.GetLength(0); // number of quadrature nodes

            // result at quadrature nodes
            var PhiAtQuadNodes = MultidimensionalArray.Create(NoOfQn);

            for (int iQn = NoOfQn - 1; iQn >= 0; iQn--)  // loop over all quadrature nodes

            {
                Y[0] = _QuadNodesGlobal[iQn, 0];
                Y[1] = _QuadNodesGlobal[iQn, 1];

                double _dist_min1 = double.MaxValue, _phi_min1 = double.NaN;
                int    _nnk_Min1 = int.MinValue, _k_min1 = int.MinValue;
                double _dist_min2 = double.MaxValue, _phi_min2 = double.NaN;
                int    _nnk_Min2 = int.MinValue, _k_min2 = int.MinValue;


                // find closest point: brute force approach
                for (int nnk = 0; nnk < NNK; nnk++)  // loop over all edges with known values

                {
                    double dist_min1 = double.MaxValue, phi_min1 = double.NaN;
                    int    nnk_Min1 = int.MinValue, k_min1 = int.MinValue;
                    double dist_min2 = double.MaxValue, phi_min2 = double.NaN;
                    int    nnk_Min2 = int.MinValue, k_min2 = int.MinValue;

                    for (int k = 0; k < K; k++)  // loop over all nodes on this edge

                    {
                        X[0] = this.CellNodesGlobal[nnk][k, 0];
                        X[1] = this.CellNodesGlobal[nnk][k, 1];
                        double phi = this.PhiEvalBuffer[nnk][0, k];
                        phi *= _sign;
                        double dist = GenericBlas.L2Dist(X, Y) + phi;

                        bool NoBlock = true;
                        if (dist < dist_min1)
                        {
                            nnk_Min2  = nnk_Min1;
                            k_min2    = k_min1;
                            dist_min2 = dist_min1;
                            phi_min2  = phi_min1;

                            dist_min1 = dist;
                            nnk_Min1  = nnk;
                            k_min1    = k;
                            phi_min1  = phi;
                            NoBlock   = false;
                        }

                        if (dist >= dist_min1 && dist < dist_min2 && NoBlock)
                        {
                            dist_min2 = dist;
                            nnk_Min2  = nnk;
                            k_min2    = k;
                            phi_min2  = phi;
                        }
                    }

                    if (dist_min1 < _dist_min1)
                    {
                        _dist_min1 = dist_min1;
                        _k_min1    = k_min1;
                        _nnk_Min1  = nnk_Min1;
                        _phi_min1  = phi_min1;

                        _dist_min2 = dist_min2;
                        _k_min2    = k_min2;
                        _nnk_Min2  = nnk_Min2;
                        _phi_min2  = phi_min2;
                    }
                }


                {
                    Debug.Assert(_nnk_Min1 == _nnk_Min2);
                    Debug.Assert(_k_min1 != _k_min2);

                    double PhiMin1 = this.PhiEvalBuffer[_nnk_Min1][0, _k_min1];
                    double PhiMin2 = this.PhiEvalBuffer[_nnk_Min2][0, _k_min2];

                    X1[0] = this.CellNodesGlobal[_nnk_Min1][_k_min1, 0];
                    X1[1] = this.CellNodesGlobal[_nnk_Min1][_k_min1, 1];

                    X2[0] = this.CellNodesGlobal[_nnk_Min2][_k_min2, 0];
                    X2[1] = this.CellNodesGlobal[_nnk_Min2][_k_min2, 1];
                }

                _dist_min1 *= _sign;

                PhiAtQuadNodes[iQn] = _dist_min1 * this.DaRuleS[iKref].Weights[iQn];
            }

            // finalize projection & return
            // ============================

            if (this.GridDat.Cells.IsCellAffineLinear(jCell))
            {
                int N  = this.LevelSetBasis_Geometric.GetLength(jCell);
                int N2 = Phi.Basis.GetLength(jCell);

                MultidimensionalArray Phi_1 = MultidimensionalArray.Create(N);
                double scale = this.GridDat.Cells.JacobiDet[jCell];
                Phi_1.Multiply(scale, BasisValues, PhiAtQuadNodes, 0.0, "m", "km", "k");
                for (int n = 0; n < N; n++)
                {
                    Phi.Coordinates[jCell, n] = Phi_1[n];
                }
                for (int n = N; n < N2; n++)
                {
                    Phi.Coordinates[jCell, n] = 0;
                }
            }
            else
            {
                throw new NotImplementedException("not implemented for curved cells");
            }

            return(true);
        }
Ejemplo n.º 19
0
        /// <summary>
        /// Quadrangulate this mesh by merging adjacent tris into quads.
        /// The algorithm will prioritise merging the longest edges first
        /// </summary>
        public void Quadrangulate()
        {
            var sortedPairs = new SortedList <double, Pair <MeshFace, MeshFace> >(Count);

            // Find adjacent pairs of tris and sort by resultant face 'squareness'
            for (int i = 0; i < Count - 1; i++)
            {
                MeshFace faceA = this[i];
                if (faceA.IsTri)
                {
                    for (int j = i + 1; j < Count; j++)
                    {
                        MeshFace faceB = this[j];
                        if (faceB.IsTri)
                        {
                            double squareness = faceA.SharedEdgeSquareness(faceB);
                            if (!squareness.IsNaN() && squareness.Abs() < 0.8)
                            {
                                sortedPairs.AddSafe(squareness, Pair.Create(faceA, faceB));
                            }
                        }
                    }
                }
            }

            // Reverse through pairs and join:
            for (int i = 0; i < sortedPairs.Count; i++)
            {
                var pair = sortedPairs.Values[i];
                if (Contains(pair.First.GUID) && Contains(pair.Second.GUID))
                {
                    Remove(pair.First);
                    Remove(pair.Second);
                    Add(pair.First.MergeWith(pair.Second));
                }
            }

            // Version 0.2: also deprecated

            /*var sortedPairs = new SortedList<double, Pair<MeshFace, MeshFace>>(Count);
             * // Find adjacent pairs of tris and sort by edge length
             * for (int i = 0; i < Count - 1; i++)
             * {
             *  MeshFace faceA = this[i];
             *  if (faceA.IsTri)
             *  {
             *      for (int j = i + 1; j < Count; j++)
             *      {
             *          MeshFace faceB = this[j];
             *          if (faceB.IsTri)
             *          {
             *              double length = faceA.SharedEdgeLengthSquared(faceB);
             *              if (length > 0)
             *                  sortedPairs.AddSafe(length, Pair.Create(faceA, faceB));
             *          }
             *      }
             *  }
             * }
             *
             * // Reverse through pairs and join:
             * for (int i = sortedPairs.Count - 1; i >= 0; i--)
             * {
             *  var pair = sortedPairs.Values[i];
             *  if (Contains(pair.First.GUID) && Contains(pair.Second.GUID))
             *  {
             *      Remove(pair.First);
             *      Remove(pair.Second);
             *      Add(pair.First.MergeWith(pair.Second));
             *  }
             * }*/

            // Version 0.1: Deprecated:

            /*
             * // Populate lists:
             * var sortedLists = new SortedList<double, IList<MeshFace>>(Count / 2);
             *
             * foreach (MeshFace face in this)
             * {
             *  if (face.IsTri)
             *  {
             *      double longEdge = face.LongestEdgeLengthSquared();
             *
             *      if (!sortedLists.ContainsKey(longEdge))
             *          sortedLists.Add(longEdge, new MeshFaceCollection());
             *
             *      sortedLists[longEdge].Add(face);
             *  }
             * }
             *
             * foreach (IList<MeshFace> faceSet in sortedLists.Values)
             * {
             *  for (int i = 0; i < faceSet.Count - 1; i++)
             *  {
             *      MeshFace faceA = faceSet[i];
             *      for (int j = i + 1; j < faceSet.Count; j++)
             *      {
             *          MeshFace faceB = faceSet[j];
             *          if (faceA.SharedVertexCount(faceB) == 2) // Has a shared edge
             *          {
             *              // Merge faces and replace:
             *              Remove(faceA);
             *              Remove(faceB);
             *              Add(faceA.MergeWith(faceB));
             *
             *              faceSet.RemoveAt(j);
             *              j = faceSet.Count;
             *          }
             *      }
             *  }
             * }
             */
        }
Ejemplo n.º 20
0
 public static double AbsoluteValue(double val)
 {
     return(val.Abs());
 }
Ejemplo n.º 21
0
        public NormalsClustering(V3d[] normalArray, double delta)
        {
            var count = normalArray.Length;

            Alloc(count);
            var ca     = m_indexArray;
            var sa     = new int[count].Set(1);
            var suma   = SumArray;
            var kdTree = normalArray.CreateRkdTreeDistDotProduct(0);
            var query  = kdTree.CreateClosestToPointQuery(delta, 0);

            for (int i = 0; i < count; i++)
            {
                int ci = ca[i]; if (ca[ci] != ci)
                {
                    do
                    {
                        ci = ca[ci];
                    } while (ca[ci] != ci); ca[i] = ci;
                }
                int si         = sa[ci];
                V3d avgNormali = suma[ci].Normalized;

                kdTree.GetClosest(query, avgNormali);
                kdTree.GetClosest(query, avgNormali.Negated);

                foreach (var id in query.List)
                {
                    int j  = (int)id.Index;
                    int cj = ca[j]; if (ca[cj] != cj)
                    {
                        do
                        {
                            cj = ca[cj];
                        } while (ca[cj] != cj); ca[j] = cj;
                    }
                    if (ci == cj)
                    {
                        continue;
                    }

                    int    sj         = sa[cj];
                    V3d    avgNormalj = suma[cj].Normalized;
                    double avgDot     = avgNormali.Dot(avgNormalj);
                    if (avgDot.Abs() < 1.0 - 2.0 * delta)
                    {
                        continue;
                    }

                    V3d sum = suma[ci] + (avgDot > 0 ? suma[cj] : suma[cj].Negated);
                    if (si < sj)
                    {
                        ca[ci] = cj; ca[i] = cj; ci = cj;
                    }
                    else
                    {
                        ca[cj] = ci; ca[j] = ci;
                    }
                    si += sj; sa[ci] = si; suma[ci] = sum;
                }
                query.Clear();
            }
            Init();
        }
Ejemplo n.º 22
0
        private void MassCorrection()
        {
            double[] Qnts_old = ComputeBenchmarkQuantities();

            CorrectionLevSet.Clear();
            CorrectionLevSet.Acc(1.0, phi);
            this.CorrectionLsTrk.UpdateTracker(0.0);

            double[] Qnts = ComputeBenchmarkQuantities();

            double massDiff = Qnts_old[0] - Qnts[0];

            // we assume the current phasefield is close to the equilibrium tangenshyperbolicus form
            SinglePhaseField phiNew  = new SinglePhaseField(phi.Basis);
            GridData         GridDat = (GridData)(phi.GridDat);
            double           mass_uc = Qnts[0];

            int i = 0;

            while (massDiff.Abs() > 1e-6)
            {
                // calculated for a cone, one could include the shape e.g. by using the circularity
                // correction guess
                double correction = Math.Sign(massDiff) * 1e-10;//-Qnts[1] / (4 * Qnts[0] * Math.PI) * massDiff * 1e-5;

                // take the correction guess and calculate a forward difference to approximate the derivative
                phiNew.ProjectField(
                    (ScalarFunctionEx) delegate(int j0, int Len, NodeSet NS, MultidimensionalArray result)
                {     // ScalarFunction2
                    Debug.Assert(result.Dimension == 2);
                    Debug.Assert(Len == result.GetLength(0));
                    int K = result.GetLength(1);     // number of nodes

                    // evaluate Phi
                    // -----------------------------
                    phi.Evaluate(j0, Len, NS, result);

                    // compute the pointwise values of the new level set
                    // -----------------------------

                    result.ApplyAll(x => 0.5 * Math.Log(Math.Max(1 + x, 1e-10) / Math.Max(1 - x, 1e-10)) * Math.Sqrt(2) * this.Control.cahn);
                    result.ApplyAll(x => Math.Tanh((x + correction) / (Math.Sqrt(2) * this.Control.cahn)));
                }
                    );

                // update LsTracker
                CorrectionLevSet.Clear();
                CorrectionLevSet.Acc(1.0, phiNew);
                this.CorrectionLsTrk.UpdateTracker(0.0);

                Qnts = ComputeBenchmarkQuantities();

                correction = -(massDiff) / ((Qnts_old[0] - Qnts[0] - massDiff) / (correction));

                double initial  = massDiff;
                bool   finished = false;
                int    k        = 0;
                //while (massDiff.Abs() - initial.Abs() >= 0.0 && step > 1e-12)
                while (!finished)
                {
                    double step = Math.Pow(0.5, k);
                    // compute and project
                    // step one calculate distance field phiDist = 0.5 * log(Max(1+c, eps)/Max(1-c, eps)) * sqrt(2) * Cahn
                    // step two project the new phasefield phiNew = tanh((cDist + correction)/(sqrt(2) * Cahn))
                    // ===================
                    phiNew.ProjectField(
                        (ScalarFunctionEx) delegate(int j0, int Len, NodeSet NS, MultidimensionalArray result)
                    {     // ScalarFunction2
                        Debug.Assert(result.Dimension == 2);
                        Debug.Assert(Len == result.GetLength(0));
                        int K = result.GetLength(1);     // number of nodes

                        // evaluate Phi
                        // -----------------------------
                        phi.Evaluate(j0, Len, NS, result);

                        // compute the pointwise values of the new level set
                        // -----------------------------

                        result.ApplyAll(x => 0.5 * Math.Log(Math.Max(1 + x, 1e-10) / Math.Max(1 - x, 1e-10)) * Math.Sqrt(2) * this.Control.cahn);
                        result.ApplyAll(x => Math.Tanh((x + correction * step) / (Math.Sqrt(2) * this.Control.cahn)));
                    }
                        );

                    // update LsTracker
                    CorrectionLevSet.Clear();
                    CorrectionLevSet.Acc(1.0, phiNew);
                    this.CorrectionLsTrk.UpdateTracker(0.0);

                    Qnts     = ComputeBenchmarkQuantities();
                    massDiff = Qnts_old[0] - Qnts[0];

                    if (massDiff.Abs() < (1 - 1e-4 * step) * initial.Abs())
                    {
                        finished = true;

                        // update field
                        phi.Clear();
                        phi.Acc(1.0, phiNew);

                        // update LsTracker
                        CorrectionLevSet.Clear();
                        CorrectionLevSet.Acc(1.0, phi);
                        this.CorrectionLsTrk.UpdateTracker(0.0);
                        Console.WriteLine($"" +
                                          $"converged with stepsize:  {step}, correction: {correction}\n" +
                                          $"                     dM:  {massDiff}");
                        if (k > 0)
                        {
                            Console.WriteLine($"Finished Linesearch in {k} iterations");
                        }
                    }
                    else if (Math.Abs(correction * step) < 1e-15)
                    {
                        // reset LsTracker
                        CorrectionLevSet.Clear();
                        CorrectionLevSet.Acc(1.0, phi);
                        this.CorrectionLsTrk.UpdateTracker(0.0);

                        Qnts     = ComputeBenchmarkQuantities();
                        massDiff = Qnts_old[0] - Qnts[0];

                        Console.WriteLine($" Linesearch failed after {k} iterations");
                        goto Failed;
                    }
                    else
                    {
                        k++;
                    }
                }
                i++;
            }

Failed:

            Console.WriteLine($"Performed Mass Correction in {i} iteratins: \n" +
                              $"\told mass:           {Qnts_old[0]:N4}\n" +
                              $"\tuncorrected mass:   {mass_uc:N4}\n" +
                              $"\tcorrected mass:     {Qnts[0]:N4}");
        }
Ejemplo n.º 23
0
        /// <summary>
        /// Solution of the extension problem on a single cell in the far-region
        /// </summary>
        /// <param name="Phi">Input;</param>
        /// <param name="GradPhi">Input;</param>
        /// <param name="ExtProperty"></param>
        /// <param name="ExtPropertyMin">Input/Output: lower threshold.</param>
        /// <param name="ExtPropertyMax">Input/Output: upper threshold.</param>
        /// <param name="jCell"></param>
        /// <param name="Accepted"></param>
        /// <param name="signMod"></param>
        public void ExtVelSolve_Far(SinglePhaseField Phi, VectorField <SinglePhaseField> GradPhi, ConventionalDGField ExtProperty, ref double ExtPropertyMin, ref double ExtPropertyMax, int jCell, CellMask Accepted, double signMod)
        {
            GridData gDat = (GridData)(Phi.GridDat);

            Debug.Assert(signMod.Abs() == 1.0);
            Debug.Assert(ExtPropertyMin <= ExtPropertyMax);


            // define cell- and edge-mask for re-compute
            // =========================================

            CellMask cM = new CellMask(gDat, Chunk.GetSingleElementChunk(jCell));

            int[] Edges = gDat.iLogicalCells.Cells2Edges[jCell].CloneAs();
            for (int i = 0; i < Edges.Length; i++)
            {
                Edges[i] = Math.Abs(Edges[i]) - 1;
            }

            EdgeMask eM = new EdgeMask(gDat, FromIndEnum(Edges, gDat.iLogicalEdges.Count)); // won't scale.

            // solve the linear extension problem for 'jCell', eventually increase
            // diffusion until we are satisfied with the solution
            // ===================================================================

            bool   MaximumPrincipleFulfilled = false;
            double DiffusionCoeff = 0; // initially: try without diffusion
            double mini = double.NaN, maxi = double.NaN;
            int    count = 0;

            while (MaximumPrincipleFulfilled == false)  // as long as we are satisfied with the solution
            {
                count++;

                // compute operator in 'jCell'
                // ---------------------------

                int N   = ExtProperty.Basis.GetLength(jCell);
                int i0G = ExtProperty.Mapping.GlobalUniqueCoordinateIndex(0, jCell, 0);
                int i0L = ExtProperty.Mapping.GlobalUniqueCoordinateIndex(0, jCell, 0);

                for (int n = 0; n < N; n++)
                {
                    this.m_ExtvelMatrix.ClearRow(i0G + n);
                    this.m_ExtvelAffine[i0L + n] = 0;
                }

                double penaltyBase = ((double)(ExtProperty.Basis.Degree + 1)).Pow2();
                var    Flux        = new ExtensionVelocityForm(Accepted.GetBitMask(), signMod, penaltyBase, gDat.Cells.h_min, jCell, DiffusionCoeff);
                var    op          = (Flux).Operator(DegreeOfNonlinearity: 2);

                // increase diffusion coefficient for next cycle
                if (DiffusionCoeff == 0)
                {
                    DiffusionCoeff = 1.0e-3; // should this be minus or plus?
                }
                else
                {
                    DiffusionCoeff *= 10;
                }

                op.ComputeMatrixEx(ExtProperty.Mapping, ArrayTools.Cat <DGField>(new DGField[] { ExtProperty, Phi }, GradPhi), ExtProperty.Mapping,
                                   this.m_ExtvelMatrix, this.m_ExtvelAffine,
                                   OnlyAffine: false,
                                   volQuadScheme: (new CellQuadratureScheme(true, cM)),
                                   edgeQuadScheme: (new EdgeQuadratureScheme(true, eM)),
                                   ParameterMPIExchange: false);

                // extract operator matrix and RHS
                // -------------------------------

                // the matrix must only have entries in the block-diagonal!

                MultidimensionalArray Mtx = MultidimensionalArray.Create(N, N);
                //MultidimensionalArray rhs = MultidimensionalArray.Create(N);
                double[] rhs = new double[N];

                for (int n = 0; n < N; n++)
                {
#if DEBUG
                    int      Lr;
                    int[]    row_cols = null;
                    double[] row_vals = null;
                    Lr = this.m_ExtvelMatrix.GetRow(i0G + n, ref row_cols, ref row_vals);
                    for (int lr = 0; lr < Lr; lr++)
                    {
                        int    ColIndex = row_cols[lr];
                        double Value    = row_vals[lr];
                        Debug.Assert((ColIndex >= i0G && ColIndex < i0G + N) || (Value == 0.0), "Matrix is expected to be block-diagonal.");
                    }
#endif
                    for (int m = 0; m < N; m++)
                    {
                        Mtx[n, m] = this.m_ExtvelMatrix[i0G + n, i0G + m];
                    }
                    rhs[n] = -this.m_ExtvelAffine[i0L + n];
                }

                // Solve the system, i.e. the local extension-velocity equation
                // ------------------------------------------------------------

                double[] ep = new double[N];
                Mtx.Solve(ep, rhs);

                for (int n = 0; n < N; n++)
                {
                    ExtProperty.Coordinates[jCell, n] = ep[n];
                }

                // detect violation of maximum principle
                // -------------------------------------

                ExtProperty.GetExtremalValuesInCell(out mini, out maxi, jCell);

                // define relaxed bounds...
                double compExtPropertyMin = ExtPropertyMin - (1.0e-8 + ExtPropertyMax - ExtPropertyMin) * 0.2;
                double compExtPropertyMax = ExtPropertyMax + (1.0e-8 + ExtPropertyMax - ExtPropertyMin) * 0.2;

                // test if extension velocity solution is within bounds
                MaximumPrincipleFulfilled = (mini >= compExtPropertyMin) && (maxi <= compExtPropertyMax);

                if (count > 5)
                {
                    break;
                }
            }
            if (count > 4)
            {
                Console.WriteLine(" ExtVel, cell #{0}, Diff coeff {1}, extremal p. holds? {2} (min/max soll = {3:e4}/{4:e4}, ist = {5:e4}/{6:e4})", jCell, DiffusionCoeff, MaximumPrincipleFulfilled, ExtPropertyMin, ExtPropertyMax, mini, maxi);
            }

            // record maxima and minima
            // ========================
            ExtPropertyMax = Math.Max(ExtPropertyMax, maxi);
            ExtPropertyMin = Math.Min(ExtPropertyMin, mini);
        }
Ejemplo n.º 24
0
        static void JacobianTest(Cell cl, out bool PositiveJacobianFlag, out bool NegativeJacobianFlag, out bool Linear)
        {
            RefElement Kref = cl.Type.GetRefElement();

            int D = 3; // for OpenFOAM, we assume 3D;

            // get nodes within ref element, to test the Jacobian
            int deg = Kref.GetInterpolationDegree(cl.Type);

            if (deg > 1)
            {
                deg--;
            }
            deg *= 3;

            NodeSet TestNodes = Kref.GetQuadratureRule(2 * deg).Nodes;

            // evaluate derivatives of nodal polynomials for transformation
            PolynomialList[]        Deriv     = Kref.GetInterpolationPolynomials1stDeriv(cl.Type);
            MultidimensionalArray[] DerivEval = new MultidimensionalArray[D];
            for (int d = 0; d < D; d++)
            {
                DerivEval[d] = Deriv[d].Values.GetValues(TestNodes);
            }

            // evaluate Jacobian matrix
            MultidimensionalArray Jacobi = MultidimensionalArray.Create(TestNodes.NoOfNodes, D, D); // temporary storage for Jacobian matrix

            Debug.Assert(cl.TransformationParams.Dimension == 2);
            Debug.Assert(cl.TransformationParams.GetLength(1) == 3);

            for (int d1 = 0; d1 < D; d1++)
            {
                Debug.Assert(cl.TransformationParams.GetLength(0) == Deriv[d1].Count);
                MultidimensionalArray JacobiCol = Jacobi.ExtractSubArrayShallow(-1, -1, d1);
                JacobiCol.Multiply(1.0, DerivEval[d1], cl.TransformationParams, 0.0, "kd", "kn", "nd");
            }

            // do the tests
            NegativeJacobianFlag = false;
            PositiveJacobianFlag = false;
            double MinAbsJacobiDet = double.MaxValue;
            double MaxAbsJacobiDet = 0.0;

            for (int n = 0; n < TestNodes.NoOfNodes; n++)
            {
                double detJac = Jacobi.ExtractSubArrayShallow(n, -1, -1).Determinant();
                if (detJac <= 0)
                {
                    NegativeJacobianFlag = true;
                }
                if (detJac > 0)
                {
                    PositiveJacobianFlag = true;
                }

                MinAbsJacobiDet = Math.Min(MinAbsJacobiDet, detJac.Abs());
                MaxAbsJacobiDet = Math.Max(MaxAbsJacobiDet, detJac.Abs());
            }

            if ((MaxAbsJacobiDet - MinAbsJacobiDet) / MinAbsJacobiDet <= 1.0e-8)
            {
                Linear = true;
            }
            else
            {
                Linear = false;
            }
        }
Ejemplo n.º 25
0
            /// <summary>
            /// Uses a safe-guarded Newton method to find all roots on
            /// <paramref name="segment"/>
            /// </summary>
            /// <param name="segment"></param>
            /// <param name="levelSet"></param>
            /// <param name="cell"></param>
            /// <param name="iKref"></param>
            /// <returns></returns>
            public double[] GetRoots(LineSegment segment, ILevelSet levelSet, int cell, int iKref)
            {
                LevelSet levelSetField = levelSet as LevelSet;

                if (levelSetField == null)
                {
                    throw new NotImplementedException("Method currently only works for polynomial level sets");
                }

                int maxNoOfCoefficientsPerDimension = levelSetField.Basis.Degree + 1;
                int noOfPolynomials = segment.ProjectedPolynomialCoefficients.GetLength(1);

                double[] coefficients = new double[maxNoOfCoefficientsPerDimension];
                for (int i = 0; i < noOfPolynomials; i++)
                {
                    double dgCoefficient = levelSetField.Coordinates[cell, i];
                    for (int j = 0; j < maxNoOfCoefficientsPerDimension; j++)
                    {
                        coefficients[j] += dgCoefficient * segment.ProjectedPolynomialCoefficients[iKref, i, j];
                    }
                }
                //if(coefficients.L2NormPow2() < this.Tolerance) {
                //    // ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
                //    // special case :
                //    // the zero-level-set is probably parallel to this line segment
                //    // ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
                //    return new double[] { -1.0, 1.0 };
                //}

                double[] roots;
                unsafe
                {
                    fixed(double *pCoeff = &coefficients[coefficients.Length - 1])
                    {
                        double xLow  = -1.0;
                        double xHigh = 1.0;

                        int           NO_OF_BRACKETS = 8;
                        List <double> lowerBounds    = new List <double>();
                        List <double> upperBounds    = new List <double>();
                        double        dx2            = 2.0 / NO_OF_BRACKETS;
                        double        x    = xLow;
                        double        fOld = Eval(x, pCoeff, coefficients.Length);

                        for (int i = 0; i < NO_OF_BRACKETS; i++)
                        {
                            x += dx2;
                            double fNew = Eval(x, pCoeff, coefficients.Length);

                            if (i == 0 && fOld.Abs() < Tolerance)
                            {
                                lowerBounds.Add(x - dx2);
                                upperBounds.Add(x);
                                fOld = fNew;
                                continue;
                            }
                            else
                            {
                                if (fNew.Abs() < Tolerance)
                                {
                                    lowerBounds.Add(x - dx2);
                                    upperBounds.Add(x);

                                    x   += dx2;
                                    fOld = Eval(x, pCoeff, coefficients.Length);
                                    continue;
                                }
                            }

                            if (fNew * fOld <= 0.0)
                            {
                                lowerBounds.Add(x - dx2);
                                upperBounds.Add(x);
                            }
                            fOld = fNew;
                        }

                        // Actual Newton-Raphson
                        int MAX_ITERATIONS = 50;

                        roots = new double[lowerBounds.Count];
                        for (int j = 0; j < lowerBounds.Count; j++)
                        {
                            xLow  = lowerBounds[j];
                            xHigh = upperBounds[j];

                            double fLeft  = Eval(xLow, pCoeff, coefficients.Length);
                            double fRight = Eval(xHigh, pCoeff, coefficients.Length);

                            if (fLeft.Abs() < Tolerance)
                            {
                                roots[j] = xLow;
                                break;
                            }

                            if (fRight.Abs() < Tolerance)
                            {
                                roots[j] = xHigh;
                                break;
                            }

                            if (fLeft.Sign() == fRight.Sign())
                            {
                                throw new Exception();
                            }

                            if (fLeft > 0.0)
                            {
                                xLow  = upperBounds[j];
                                xHigh = lowerBounds[j];
                            }

                            double root = 0.5 * (xLow + xHigh);
                            double f;
                            double df;
                            Eval(root, pCoeff, coefficients.Length, out f, out df);

                            double dxOld = (xHigh - xLow).Abs();
                            double dx    = dxOld;

                            int i = 0;
                            while (true)
                            {
                                if (i > MAX_ITERATIONS)
                                {
                                    throw new Exception("Max iterations exceeded");
                                }

                                double a = ((root - xHigh) * df - f) * ((root - xLow) * df - f);
                                if (a > 0.0 || 2.0 * Math.Abs(f) > Math.Abs(dxOld * df))
                                {
                                    // Newton out of range or too slow -> Bisect
                                    dxOld = dx;
                                    dx    = 0.5 * (xHigh - xLow);
                                    root  = xLow + dx;
                                }
                                else
                                {
                                    // Take Newton step
                                    dxOld = dx;
                                    dx    = -f / df;

                                    //// Convergence acceleration according to Yao2014
                                    //double fDelta = Eval(root + dx, pCoeff, coefficients.Length);
                                    //dx = -(f + fDelta) / df;

                                    root += dx;
                                }

                                Eval(root, pCoeff, coefficients.Length, out f, out df);

                                if (Math.Abs(f) <= Tolerance)
                                {
                                    roots[j] = root;
                                    break;
                                }

                                if (f < 0.0)
                                {
                                    xLow = root;
                                }
                                else
                                {
                                    xHigh = root;
                                }

                                i++;
                            }
                        }
                    }
                }

                return(roots);
            }
Ejemplo n.º 26
0
        /// <summary>
        /// Intersection of line <paramref name="S1"/>--<paramref name="S2"/> and <paramref name="E1"/>--<paramref name="E2"/>
        /// </summary>
        /// <param name="S1"></param>
        /// <param name="S2"></param>
        /// <param name="E1"></param>
        /// <param name="E2"></param>
        /// <param name="alpha1">
        /// coordinate of <paramref name="I"/> on the line <paramref name="S1"/>--<paramref name="S2"/>
        /// </param>
        /// <param name="alpha2">
        /// coordinate of <paramref name="I"/> on the line <paramref name="E1"/>--<paramref name="E2"/>
        /// </param>
        /// <param name="I"></param>
        /// <returns></returns>
        internal static bool ComputeIntersection(Vector S1, Vector S2, Vector E1, Vector E2, out double alpha1, out double alpha2, out Vector I)
        {
            if (S1.Dim != 2)
            {
                throw new ArgumentException("spatial dimension mismatch.");
            }
            if (S2.Dim != 2)
            {
                throw new ArgumentException("spatial dimension mismatch.");
            }
            if (E1.Dim != 2)
            {
                throw new ArgumentException("spatial dimension mismatch.");
            }
            if (E2.Dim != 2)
            {
                throw new ArgumentException("spatial dimension mismatch.");
            }

            Vector S12 = S2 - S1;
            Vector E12 = E2 - E1;

            if (S12.Abs() <= 0)
            {
                throw new ArgumentException();
            }
            if (E12.Abs() <= 0)
            {
                throw new ArgumentException();
            }


            var P_S12 = AffineManifold.FromPoints(S1, S2);
            var P_E12 = AffineManifold.FromPoints(E1, E2);

            Vector NS = P_S12.Normal; NS.Normalize();
            Vector NE = P_E12.Normal; NE.Normalize();

            double parallel = NS * NE;

            if (parallel.Abs() >= 1.0)
            {
                alpha1 = double.PositiveInfinity;
                alpha2 = double.PositiveInfinity;
                I      = new Vector(double.PositiveInfinity, double.PositiveInfinity);
                return(false);
            }

            //S12.Normalize();
            //E12.Normalize();

            I = AffineManifold.Intersect2D(P_S12, P_E12);

            Vector IS1 = I - S2;
            Vector IE1 = I - E2;
            Vector IS2 = I - S1;
            Vector IE2 = I - E1;

            Vector IS;
            bool   flip_1;

            if (IS1.AbsSquare() > IS2.AbsSquare())
            {
                IS     = IS1;
                flip_1 = true;
            }
            else
            {
                IS     = IS2;
                flip_1 = false;
            }

            Vector IE;
            bool   flip_2;

            if (IE1.AbsSquare() > IE2.AbsSquare())
            {
                IE     = IE1;
                flip_2 = true;
            }
            else
            {
                IE     = IE2;
                flip_2 = false;
            }

            Debug.Assert((S12.AngleTo(IS).Abs() <= 1.0e-5) || ((S12.AngleTo(IS).Abs() - Math.PI).Abs() <= 1.0e-5));
            Debug.Assert((E12.AngleTo(IE).Abs() <= 1.0e-5) || ((E12.AngleTo(IE).Abs() - Math.PI).Abs() <= 1.0e-5));

            alpha1 = (S12 * IS) / S12.AbsSquare();
            alpha2 = (E12 * IE) / E12.AbsSquare();

            if (flip_1)
            {
                alpha1 = 1 + alpha1;
            }
            if (flip_2)
            {
                alpha2 = 1 + alpha2;
            }

            return(true);
        }
Ejemplo n.º 27
0
 public void Abs_ShouldBehaveAsMathAbs_IfDouble(double value) => Assert.Equal(Math.Abs(value), value.Abs());
Ejemplo n.º 28
0
 public static int SignedRoundToInt(this double x)
 {
     return(x.Sign() * x.Abs().RoundToInt());
 }
Ejemplo n.º 29
0
 internal void OnAddMyTrade(string portfolio, string securityId, string orderId, double price, double amount, DateTime time, string tradeNo)
 {
     NewMyTrade.SafeInvoke(portfolio, securityId, orderId.To <long>(), price.ToDecimal(), amount.Abs().ToDecimal(), time, tradeNo.To <long>());
 }
Ejemplo n.º 30
0
 public static int Sign(this double v)
 {
     return(v.Abs() < Epsilon ? 0 : Math.Sign(v));
 }