/// <summary>
/// Extract a single layer from a 3D dfsu file, and write it to a 2D dfsu file.
/// <para>
/// If a layer value does not exist for a certain 2D element, delete value is written
/// to the 2D resut file. This is relevant for Sigma-Z type of files.
/// </para>
/// </summary>
/// <param name="filenameDfsu3">Name of 3D dfsu source file</param>
/// <param name="filenameDfsu2">Name of 2D dfsu result file</param>
/// <param name="layerNumber">Layer to extract.
/// <para>
/// Positive values count from bottom up i.e. 1 is bottom layer, 2 is second layer from bottom etc.
/// </para>
/// <para>
/// Negative values count from top down, i.e. -1 is toplayer, -2 is second layer from top etc.
/// </para>
/// </param>
public static void ExtractDfsu2DLayerFrom3D(string filenameDfsu3, string filenameDfsu2, int layerNumber)
{
IDfsuFile dfsu3File = DfsFileFactory.DfsuFileOpen(filenameDfsu3);
// Check that dfsu3 file is a 3D dfsu file.
switch (dfsu3File.DfsuFileType)
{
case DfsuFileType.Dfsu2D:
case DfsuFileType.DfsuVerticalColumn:
case DfsuFileType.DfsuVerticalProfileSigma:
case DfsuFileType.DfsuVerticalProfileSigmaZ:
throw new InvalidOperationException("Input file is not a 3D dfsu file");
}
// Calculate offset from toplayer element. Offset is between 0 (top layer) and
// dfsu3File.NumberOfLayers-1 (bottom layer)
int topLayerOffset;
if (layerNumber > 0 && layerNumber <= dfsu3File.NumberOfLayers)
{
topLayerOffset = dfsu3File.NumberOfLayers - layerNumber;
}
else if (layerNumber < 0 && -layerNumber <= dfsu3File.NumberOfLayers)
{
topLayerOffset = -layerNumber - 1;
}
else
{
throw new ArgumentException("Layer number is out of range");
}
double[] xv = dfsu3File.X;
double[] yv = dfsu3File.Y;
float[] zv = dfsu3File.Z;
int[] cv = dfsu3File.Code;
// --------------------------------------------------
// Create 2D mesh from 3D mesh
// List of new 2D nodes
int node2DCount = 0;
List <double> xv2 = new List <double>();
List <double> yv2 = new List <double>();
List <float> zv2 = new List <float>();
List <int> cv2 = new List <int>();
// Renumbering array, from 3D node numbers to 2D node numbers
// i.e. if a 3D element refers to node number k, the 2D element node number is renumber[k]
int[] renumber = new int[dfsu3File.NumberOfNodes];
// Coordinates of last created node
double xr2 = -1e-10;
double yr2 = -1e-10;
// Create 2D nodes, by skipping nodes with equal x,y coordinates
for (int i = 0; i < dfsu3File.NumberOfNodes; i++)
{
// If 3D x,y coordinates are equal to the last created 2D node,
// map this node to the last created 2D node, otherwise
// create new 2D node and map to that one
if (xv[i] != xr2 || yv[i] != yr2)
{
// Create new node
node2DCount++;
xr2 = xv[i];
yr2 = yv[i];
float zr2 = zv[i];
int cr2 = cv[i];
xv2.Add(xr2);
yv2.Add(yr2);
zv2.Add(zr2);
cv2.Add(cr2);
}
// Map this 3D node to the last created 2D node.
renumber[i] = node2DCount;
}
// Find indices of top layer elements
IList <int> topLayer = dfsu3File.FindTopLayerElements();
// Create element table for 2D dfsu file
int[][] elmttable2 = new int[topLayer.Count][];
for (int i = 0; i < topLayer.Count; i++)
{
// 3D element nodes
int[] elmt3 = dfsu3File.ElementTable[topLayer[i]];
// 2D element nodes, only half as big, so copy over the first half
int[] elmt2 = new int[elmt3.Length / 2];
for (int j = 0; j < elmt2.Length; j++)
{
elmt2[j] = renumber[elmt3[j]];
}
elmttable2[i] = elmt2;
}
// --------------------------------------------------
// Create 2D dfsu file
DfsuBuilder builder = DfsuBuilder.Create(DfsuFileType.Dfsu2D);
// Setup header and geometry
builder.SetNodes(xv2.ToArray(), yv2.ToArray(), zv2.ToArray(), cv2.ToArray());
builder.SetElements(elmttable2);
builder.SetProjection(dfsu3File.Projection);
builder.SetTimeInfo(dfsu3File.StartDateTime, dfsu3File.TimeStepInSeconds);
if (dfsu3File.ZUnit == eumUnit.eumUUnitUndefined)
{
builder.SetZUnit(eumUnit.eumUmeter);
}
else
{
builder.SetZUnit(dfsu3File.ZUnit);
}
// Add dynamic items, copying from source, though not the first one, if it
// contains the z-variation on the nodes
for (int i = 0; i < dfsu3File.ItemInfo.Count; i++)
{
IDfsSimpleDynamicItemInfo itemInfo = dfsu3File.ItemInfo[i];
if (itemInfo.ElementCount == dfsu3File.NumberOfElements)
{
builder.AddDynamicItem(itemInfo.Name, itemInfo.Quantity);
}
}
// Create file
DfsuFile dfsu2File = builder.CreateFile(filenameDfsu2);
// --------------------------------------------------
// Process data
// Check if the layer number exists for 2D element, i.e. if that element
// in 2D has that number of columnes in the 3D (relevant for sigma-z files)
// If elementExists[i] is false, write delete value to file
bool[] elementExists = new bool[topLayer.Count];
int numLayersInColumn = topLayer[0] + 1;
elementExists[0] = (numLayersInColumn - topLayerOffset) > 0;
for (int i = 1; i < topLayer.Count; i++)
{
numLayersInColumn = (topLayer[i] - topLayer[i - 1]);
elementExists[i] = (numLayersInColumn - topLayerOffset) > 0;
}
// For performance, use predefined itemdata objects when reading data from dfsu 3D file
IDfsItemData <float>[] dfsu3ItemDatas = new IDfsItemData <float> [dfsu3File.ItemInfo.Count];
for (int j = 0; j < dfsu3File.ItemInfo.Count; j++)
{
dfsu3ItemDatas[j] = (IDfsItemData <float>)dfsu3File.ItemInfo[j].CreateEmptyItemData();
}
// Float data to write to dfsu 2D file
float[] data2 = new float[dfsu2File.NumberOfElements];
float deleteValueFloat = dfsu2File.DeleteValueFloat;
for (int i = 0; i < dfsu3File.NumberOfTimeSteps; i++)
{
for (int j = 0; j < dfsu3File.ItemInfo.Count; j++)
{
// Read data from 3D dfsu
IDfsItemData <float> data3Item = dfsu3ItemDatas[j];
bool ok = dfsu3File.ReadItemTimeStep(data3Item, i);
// 3D data
float[] data3 = data3Item.Data;
// Skip any items not having size = NumberOfElments (the z-variation on the nodes)
if (data3.Length != dfsu3File.NumberOfElements)
{
continue;
}
// Loop over all 2D elements
for (int k = 0; k < topLayer.Count; k++)
{
// Extract layer data from 3D column into 2D element value
if (elementExists[k])
{
data2[k] = data3[topLayer[k] - topLayerOffset];
}
else
{
data2[k] = deleteValueFloat;
}
}
dfsu2File.WriteItemTimeStepNext(data3Item.Time, data2);
}
}
dfsu3File.Close();
dfsu2File.Close();
}
/// <summary>
/// Create dfsu and mesh file from dfs2 file.
/// <para>
/// Note 1: Boundary code is set to land value at
/// all boundaries of mesh and dfsu file.
/// These must be updated to something "better"
/// if to use as input in another simulation.
/// </para>
/// <para>
/// Note 2: P and Q values are not rotated with the
/// grid, but should be so, if used in the
/// projected coordinate system. It must take
/// the 327 degrees rotation into account.
/// </para>
/// </summary>
/// <param name="dfs2Filename">Name of input dfs2 file, e.g. the OresundHD.dfs2</param>
/// <param name="meshFilename">Name of output mesh file</param>
/// <param name="dfsuFilename">Name of output dfsu file</param>
public static void CreateDfsuFromDfs2(string dfs2Filename, string meshFilename, string dfsuFilename)
{
// Open file
Dfs2File dfs2 = DfsFileFactory.Dfs2FileOpen(dfs2Filename);
// Read bathymetry from first static item
IDfsStaticItem bathymetryItem = dfs2.ReadStaticItemNext();
float[] bathymetry = (float[])bathymetryItem.Data;
// Extract spatial axis
IDfsAxisEqD2 spatialAxis = (IDfsAxisEqD2)dfs2.SpatialAxis;
// Some convenience variables
double dx = spatialAxis.Dx;
double dy = spatialAxis.Dy;
double x0 = spatialAxis.X0;
double y0 = spatialAxis.Y0;
int xCount = spatialAxis.XCount;
int yCount = spatialAxis.YCount;
// First custom block (index 0) contains the M21_MISC values,
// where the 4th (index 3) is the land value
float landValue = (float)dfs2.FileInfo.CustomBlocks[0][3];
//-----------------------------------------
// Find out which elements in the dfs2 grid that is not a land value
// and include all those elements and their surrounding nodes in mesh
// Arrays indicating if element and node in grid is used or not in mesh
bool[,] elmts = new bool[xCount, yCount];
int[,] nodes = new int[xCount + 1, yCount + 1];
// Loop over all elements in 2D grid
for (int l = 0; l < yCount; l++)
{
for (int k = 0; k < xCount; k++)
{
// If bathymetry is not land value, use element.
if (bathymetry[k + l * xCount] != landValue)
{
// element [l,k] is used, and also the 4 nodes around it
elmts[k, l] = true;
nodes[k, l] = 1;
nodes[k + 1, l] = 1;
nodes[k, l + 1] = 1;
nodes[k + 1, l + 1] = 1;
}
}
}
//-----------------------------------------
// Create new mest nodes
// Cartography object can convert grid (x,y) to projection (east,north)
IDfsProjection proj = dfs2.FileInfo.Projection;
DHI.Projections.Cartography cart = new DHI.Projections.Cartography(proj.WKTString, proj.Longitude, proj.Latitude, proj.Orientation);
// New mesh nodes
List <double> X = new List <double>();
List <double> Y = new List <double>();
List <float> Zf = new List <float>(); // float values for dfsu file
List <double> Zd = new List <double>(); // double values for mesh file
List <int> Code = new List <int>();
// Loop over all nodes
int nodesCount = 0;
for (int l = 0; l < yCount + 1; l++)
{
for (int k = 0; k < xCount + 1; k++)
{
// Check if node is included in mesh
if (nodes[k, l] > 0)
{
// Convert from mesh (x,y) to projection (east,north)
double east, north;
cart.Xy2Proj((k - 0.5) * dx + x0, (l - 0.5) * dy + y0, out east, out north);
// Average Z on node from neighbouring grid cell values, cell value is used
// unless they are outside grid or has land values
double z = 0;
int zCount = 0;
if (k > 0 && l > 0 && bathymetry[k - 1 + (l - 1) * xCount] != landValue)
{
zCount++; z += bathymetry[k - 1 + (l - 1) * xCount];
}
if (k < xCount && l > 0 && bathymetry[k + (l - 1) * xCount] != landValue)
{
zCount++; z += bathymetry[k + (l - 1) * xCount];
}
if (k > 0 && l < yCount && bathymetry[k - 1 + (l) * xCount] != landValue)
{
zCount++; z += bathymetry[k - 1 + (l) * xCount];
}
if (k < xCount && l < yCount && bathymetry[k + (l) * xCount] != landValue)
{
zCount++; z += bathymetry[k + (l) * xCount];
}
if (zCount > 0)
{
z /= zCount;
}
else
{
z = landValue;
}
// Store new node number and add node
nodesCount++;
nodes[k, l] = nodesCount; // this is the node number to use in the element table
X.Add(east);
Y.Add(north);
Zf.Add((float)z);
Zd.Add(z);
Code.Add(zCount == 4 ? 0 : 1); // Land boundary if zCount < 4
}
}
}
// New mesh elements
List <int[]> elmttable2 = new List <int[]>();
for (int l = 0; l < yCount; l++)
{
for (int k = 0; k < xCount; k++)
{
// Check if element is included in mesh
if (elmts[k, l])
{
// For this element, add the four surrounding nodes,
// counter-clockwise order
int[] newNodes = new int[4];
newNodes[0] = nodes[k, l];
newNodes[1] = nodes[k + 1, l];
newNodes[2] = nodes[k + 1, l + 1];
newNodes[3] = nodes[k, l + 1];
elmttable2.Add(newNodes);
}
}
}
//-----------------------------------------
// Create mesh
{
// Create 2D dfsu file
MeshBuilder builder = new MeshBuilder();
// Setup header and geometry
builder.SetNodes(X.ToArray(), Y.ToArray(), Zd.ToArray(), Code.ToArray());
builder.SetElements(elmttable2.ToArray());
builder.SetProjection(dfs2.FileInfo.Projection);
// Create new file
MeshFile mesh = builder.CreateMesh();
mesh.Write(meshFilename);
}
//-----------------------------------------
// Create dfsu file
{
// dfs2 time axis
IDfsEqCalendarAxis timeAxis = (IDfsEqCalendarAxis)dfs2.FileInfo.TimeAxis;
// Create 2D dfsu file
DfsuBuilder builder = DfsuBuilder.Create(DfsuFileType.Dfsu2D);
// Setup header and geometry
builder.SetNodes(X.ToArray(), Y.ToArray(), Zf.ToArray(), Code.ToArray());
builder.SetElements(elmttable2.ToArray());
builder.SetProjection(dfs2.FileInfo.Projection);
builder.SetTimeInfo(timeAxis.StartDateTime, timeAxis.TimeStepInSeconds());
builder.SetZUnit(eumUnit.eumUmeter);
// Add dynamic items, copying from dfs2 file
for (int i = 0; i < dfs2.ItemInfo.Count; i++)
{
IDfsSimpleDynamicItemInfo itemInfo = dfs2.ItemInfo[i];
builder.AddDynamicItem(itemInfo.Name, itemInfo.Quantity);
}
// Create new file
DfsuFile dfsu = builder.CreateFile(dfsuFilename);
// Add dfs2 data to dfsu file
float[] dfsuData = new float[dfsu.NumberOfElements];
for (int i = 0; i < dfs2.FileInfo.TimeAxis.NumberOfTimeSteps; i++)
{
for (int j = 0; j < dfs2.ItemInfo.Count; j++)
{
// Read dfs2 grid data
IDfsItemData2D <float> itemData = (IDfsItemData2D <float>)dfs2.ReadItemTimeStep(j + 1, i);
// Extract 2D grid data to dfsu data array
int lk = 0;
for (int l = 0; l < yCount; l++)
{
for (int k = 0; k < xCount; k++)
{
if (elmts[k, l])
{
dfsuData[lk++] = itemData[k, l];
}
}
}
// write data
dfsu.WriteItemTimeStepNext(itemData.Time, dfsuData);
}
}
dfsu.Close();
}
dfs2.Close();
}
/// <summary>
/// Example on how to extract dfs0 data from a 2D dfsu file for certain elements. All items
/// from dfsu file are extracted.
/// </summary>
/// <param name="dfsuFileNamePath">Name, including path, of 2D dfsu file</param>
/// <param name="elmtsIndices">Indices of elements to extract data from</param>
/// <param name="useStream">Use stream when writing dfs0 files - then more than 400 files can be created simultaneously</param>
public static void ExtractDfs0FromDfsu(string dfsuFileNamePath, IList <int> elmtsIndices, bool useStream)
{
// If not using stream approach, at most 400 elements at a time can be processed.
// There is a limit on how many files you can have open at the same time using
// the standard approach. It will fail in a nasty way, if the maximum number of
// file handles are exceeded. This is not an issue when using .NET streams.
if (!useStream && elmtsIndices.Count > 400)
{
throw new ArgumentException("At most 400 elements at a time");
}
// Open source dfsu file
IDfsuFile source;
Stream stream = null;
if (useStream)
{
stream = new FileStream(dfsuFileNamePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
source = DfsuFile.Open(stream);
}
else
{
source = DfsuFile.Open(dfsuFileNamePath);
}
// Figure out "basic" dfs0 file name
string dfsuFilename = Path.GetFileNameWithoutExtension(dfsuFileNamePath);
string path = Path.GetDirectoryName(dfsuFileNamePath);
string dfs0BaseFilename = Path.Combine(path, "test_" + dfsuFilename + "-");
// Factory for creating dfs objects
DfsFactory factory = new DfsFactory();
// Create a dfs0 file for each element in elmtsIndices
DfsFile[] dfs0Files = new DfsFile[elmtsIndices.Count];
Stream[] dfs0Streams = new Stream [elmtsIndices.Count];
double timeSpan = source.TimeStepInSeconds * source.NumberOfTimeSteps;
for (int k = 0; k < elmtsIndices.Count; k++)
{
// Index of element to create dfs0 for
int elmtsIndex = elmtsIndices[k];
// Calculate element center coordinates, to be stored in dfs0 items.
// Stored as float in dfs0, hence possible loss of precision...
float x = 0, y = 0, z = 0;
int[] nodeNumbers = source.ElementTable[elmtsIndex];
for (int i = 0; i < nodeNumbers.Length; i++)
{
int nodeIndex = nodeNumbers[i] - 1; // from number to index
x += (float)source.X[nodeIndex];
y += (float)source.Y[nodeIndex];
z += source.Z[nodeIndex];
}
x /= nodeNumbers.Length;
y /= nodeNumbers.Length;
z /= nodeNumbers.Length;
// Start building dfs0 file header
DfsBuilder builder = DfsBuilder.Create("fileTitle", "appTitle", 1);
builder.SetDataType(1); // standard dfs0 value
builder.SetGeographicalProjection(source.Projection);
builder.SetTemporalAxis(factory.CreateTemporalEqCalendarAxis(eumUnit.eumUsec, source.StartDateTime, 0, source.TimeStepInSeconds));
// Add all dynamic items from dfsu file to dfs0 file
for (int j = 0; j < source.ItemInfo.Count; j++)
{
IDfsSimpleDynamicItemInfo sourceItem = source.ItemInfo[j];
DfsDynamicItemBuilder itemBuilder = builder.CreateDynamicItemBuilder();
itemBuilder.Set(sourceItem.Name, sourceItem.Quantity, sourceItem.DataType);
itemBuilder.SetAxis(factory.CreateAxisEqD0());
itemBuilder.SetValueType(sourceItem.ValueType);
itemBuilder.SetReferenceCoordinates(x, y, z); // optional
builder.AddDynamicItem(itemBuilder.GetDynamicItemInfo());
}
// Create and get file, store them in dfs0s array
string dfs0Filename = dfs0BaseFilename + (elmtsIndex).ToString("000000") + ".dfs0";
if (useStream)
{
// Create file using C# streams - necessary to provie number of time steps and timespan of data
builder.SetNumberOfTimeSteps(source.NumberOfTimeSteps);
builder.SetTimeInfo(0, timeSpan);
Stream dfs0FileStream = new FileStream(dfs0Filename, FileMode.Create, FileAccess.Write, FileShare.ReadWrite);
builder.CreateStream(dfs0FileStream);
dfs0Streams[k] = dfs0FileStream;
}
else
{
// Create file in the ordinary way. Will include statistics (of delete values etc).
builder.CreateFile(dfs0Filename);
}
dfs0Files[k] = builder.GetFile();
}
// For performance, use predefined itemdata objects when reading data from dfsu
IDfsItemData <float>[] dfsuItemDatas = new IDfsItemData <float> [source.ItemInfo.Count];
for (int j = 0; j < source.ItemInfo.Count; j++)
{
dfsuItemDatas[j] = (IDfsItemData <float>)source.ItemInfo[j].CreateEmptyItemData();
}
// Read data from dfsu and store in dfs0
float[] dfs0Data = new float[1];
for (int i = 0; i < source.NumberOfTimeSteps; i++)
{
for (int j = 0; j < source.ItemInfo.Count; j++)
{
// Read data from dfsu
IDfsItemData <float> dfsuItemData = dfsuItemDatas[j];
bool ok = source.ReadItemTimeStep(dfsuItemData, i);
float[] floats = dfsuItemData.Data;
// write data to dfs0's
for (int k = 0; k < elmtsIndices.Count; k++)
{
int elmtsIndex = elmtsIndices[k];
dfs0Data[0] = floats[elmtsIndex];
dfs0Files[k].WriteItemTimeStepNext(0, dfs0Data);
}
}
}
// Close dfsu files
source.Close();
if (stream != null)
{
stream.Close();
}
// Close all dfs0 files
for (int k = 0; k < elmtsIndices.Count; k++)
{
dfs0Files[k].Close();
if (dfs0Streams[k] != null)
{
dfs0Streams[k].Close();
}
}
}
