ucar.ma2.IndexIterator Java Examples

private Array findReferenceObjectNames(Array data) throws IOException {
  IndexIterator ii = data.getIndexIterator();

  Array newData = Array.factory(DataType.STRING, data.getShape());
  IndexIterator ii2 = newData.getIndexIterator();
  while (ii.hasNext()) {
    long objId = ii.getLongNext();
    DataObject dobj = getDataObject(objId, null);
    if (dobj == null) {
      log.warn("readReferenceObjectNames cant find obj= {}", objId);
    } else {
      if (debugReference) {
        log.debug(" Referenced object= {}", dobj.who);
      }
      ii2.setObjectNext(dobj.who);
    }
  }
  return newData;
}
 

private static void printVariableArray(Formatter out, ArrayObject array, Indent indent, CancelTask ct) {
  out.format("%n%s{", indent);
  indent.incr();
  IndexIterator iter = array.getIndexIterator();
  boolean first = true;
  while (iter.hasNext()) {
    Array data = (Array) iter.next();
    if (!first) {
      out.format(", ");
    }
    printArray(out, data, indent, ct);
    first = false;
  }
  indent.decr();
  out.format("%n%s}", indent);
}
 

@Test
public void testMissingData() throws IOException {
  Group.Builder parent = Group.builder().addDimension(Dimension.builder("dim1", 7).setIsUnlimited(true).build())
      .addDimension(new Dimension("dim2", 27));

  VariableDS vds = VariableDS.builder().setName("name").setDataType(DataType.FLOAT).setUnits("units").setDesc("desc")
      .setEnhanceMode(NetcdfDataset.getEnhanceAll()).addAttribute(new Attribute("missing_value", 0.0f))
      .setParentGroupBuilder(parent).setDimensionsByName("dim1").build(parent.build());

  Array data = vds.read();
  System.out.printf("data = %s%n", data);
  IndexIterator iter = data.getIndexIterator();
  while (iter.hasNext()) {
    assertThat(iter.getFloatNext()).isEqualTo(Float.NaN);
  }
}
 

/**
 * Read the data for the variable
 *
 * @param v2 Variable to read
 * @param section section infomation
 * @return Array of data
 * @throws IOException problem reading from file
 * @throws InvalidRangeException invalid Range
 */
public Array readData(Variable v2, Section section) throws IOException, InvalidRangeException {

  Array dataArray = Array.factory(DataType.FLOAT, section.getShape());
  GradsVariable gradsVar = findVar(v2);
  if (gradsVar == null)
    throw new IOException();

  // Canonical ordering is ens, time, level, lat, lon
  int rangeIdx = 0;
  Range ensRange = (gradsDDF.getEnsembleDimension() != null) ? section.getRange(rangeIdx++) : new Range(0, 0);
  Range timeRange = (section.getRank() > 2) ? section.getRange(rangeIdx++) : new Range(0, 0);
  Range levRange = (gradsVar.getNumLevels() > 0) ? section.getRange(rangeIdx++) : new Range(0, 0);
  Range yRange = section.getRange(rangeIdx++);
  Range xRange = section.getRange(rangeIdx);

  IndexIterator ii = dataArray.getIndexIterator();

  for (int ensIdx : ensRange)
    for (int timeIdx : timeRange)
      for (int levelIdx : levRange)
        readXY(v2, ensIdx, timeIdx, levelIdx, yRange, xRange, ii);

  return dataArray;
}
 

private double geoShiftGetXstart(Array lon, double inc) {
  Index ilon = lon.getIndex();
  int[] lonShape = lon.getShape();
  IndexIterator lonIter = lon.getIndexIterator();
  double xlon;

  LatLonPoint p0 = LatLonPoint.create(0, lon.getFloat(ilon.set(0)));
  LatLonPoint pN = LatLonPoint.create(0, lon.getFloat(ilon.set(lonShape[0] - 1)));

  xlon = p0.getLongitude();
  while (lonIter.hasNext()) {
    float l = lonIter.getFloatNext();
    LatLonPoint pn = LatLonPoint.create(0, l);
    if (pn.getLongitude() < xlon) {
      xlon = pn.getLongitude();
    }
  }

  if (p0.getLongitude() == pN.getLongitude()) {
    xlon = xlon - inc;
  }

  return xlon;
}
 

/**
 * Replace missing values with 0; scale other values between 1 and 255, return a byte data array.
 *
 * @param grid GridDatatype
 * @param data input data array
 * @return byte data array with missing values replaced and data scaled from 1- 255.
 */
private ArrayByte replaceMissingValuesAndScale(IsMissingEvaluator grid, Array data, MAMath.MinMax dataMinMax) {
  double scale = 254.0 / (dataMinMax.max - dataMinMax.min);

  ArrayByte byteArray = (ArrayByte) Array.factory(DataType.BYTE, data.getShape());
  IndexIterator dataIter = data.getIndexIterator();
  IndexIterator resultIter = byteArray.getIndexIterator();

  byte bv;
  while (dataIter.hasNext()) {
    double v = dataIter.getDoubleNext();
    if (grid.isMissing(v)) {
      bv = 0;
    } else {
      int iv = (int) ((v - dataMinMax.min) * scale + 1);
      bv = (byte) (iv & 0xff);
    }
    resultIter.setByteNext(bv);
  }

  return byteArray;
}
 

/**
 * Replace missing values with dataMinMax.min - 1.0; return a floating point data array.
 *
 * @param grid GridDatatype
 * @param data input data array
 * @return floating point data array with missing values replaced.
 */
private ArrayFloat replaceMissingValues(IsMissingEvaluator grid, Array data, MAMath.MinMax dataMinMax) {
  float minValue = (float) (dataMinMax.min - 1.0);

  ArrayFloat floatArray = (ArrayFloat) Array.factory(DataType.FLOAT, data.getShape());
  IndexIterator dataIter = data.getIndexIterator();
  IndexIterator floatIter = floatArray.getIndexIterator();
  while (dataIter.hasNext()) {
    float v = dataIter.getFloatNext();
    if (grid.isMissing((double) v)) {
      v = minValue;
    }
    floatIter.setFloatNext(v);
  }

  return floatArray;
}
 

/**
 * Read data from this ray.
 *
 * @param raf read from this file
 * @param abbrev which data type we want
 * @param gateRange handles the possible subset of data to return
 * @param ii put the data here
 */
public void readData(RandomAccessFile raf, String abbrev, Range gateRange, IndexIterator ii) throws IOException {
  long offset = rayOffset;
  offset += (getDataOffset(abbrev) * 2 - 2);
  raf.seek(offset);
  byte[] b2 = new byte[2];
  int dataCount = getGateCount(abbrev);
  byte[] data = new byte[dataCount * 2];
  raf.readFully(data);

  for (int gateIdx : gateRange) {
    if (gateIdx >= dataCount)
      ii.setShortNext(uf_header2.missing);
    else {
      b2[0] = data[gateIdx * 2];
      b2[1] = data[gateIdx * 2 + 1];
      short value = getShort(b2, 0);

      ii.setShortNext(value);
    }
  }

}
 

private Array convertToDegrees(Variable.Builder<?> vb) {
  VariableDS.Builder<?> vds = (VariableDS.Builder<?>) vb;
  Variable v = vds.orgVar;
  Array data;
  try {
    data = v.read();
    data = data.reduce();
  } catch (IOException ioe) {
    throw new RuntimeException("data read failed on " + v.getFullName() + "=" + ioe.getMessage());
  }
  IndexIterator ii = data.getIndexIterator();
  while (ii.hasNext()) {
    ii.setDoubleCurrent(Math.toDegrees(ii.getDoubleNext()));
  }
  return data;
}
 

public void readData1(RandomAccessFile raf, int datatype, Range gateRange, IndexIterator ii) throws IOException {
  long offset = message_offset;
  offset += MESSAGE_HEADER_SIZE; // offset is from "start of digital radar data message header"
  offset += getDataOffset(datatype);
  raf.seek(offset);
  if (logger.isDebugEnabled()) {
    logger.debug("  read recno " + recno + " at offset " + offset + " count= " + getGateCount(datatype));
    logger.debug(
        "   offset: reflect= " + reflect_offset + " velocity= " + velocity_offset + " spWidth= " + spectWidth_offset);
  }

  int dataCount = getGateCount(datatype);
  short[] data = new short[dataCount];
  raf.readShort(data, 0, dataCount);

  for (int idx : gateRange) {
    if (idx >= dataCount)
      ii.setShortNext((short) -32768);
    else
      ii.setShortNext(data[idx]);
  }

}
 

/**
 * Read data from this record.
 * 
 * @param raf read from this file
 * @param datatype which data type we want
 * @param gateRange handles the possible subset of data to return
 * @param ii put the data here
 */
public void readData(RandomAccessFile raf, int datatype, Range gateRange, IndexIterator ii) throws IOException {
  long offset = message_offset;
  offset += MESSAGE_HEADER_SIZE; // offset is from "start of digital radar data message header"
  offset += getDataOffset(datatype);
  raf.seek(offset);
  if (logger.isDebugEnabled()) {
    logger.debug("  read recno " + recno + " at offset " + offset + " count= " + getGateCount(datatype));
    logger.debug(
        "   offset: reflect= " + reflect_offset + " velocity= " + velocity_offset + " spWidth= " + spectWidth_offset);
  }

  int dataCount = getGateCount(datatype);
  byte[] data = new byte[dataCount];
  raf.readFully(data);

  for (int gateIdx : gateRange) {
    if (gateIdx >= dataCount)
      ii.setByteNext(MISSING_DATA);
    else
      ii.setByteNext(data[gateIdx]);
  }

}
 

protected Array convertEnums(Map<Integer, String> map, DataType dataType, Array values) {
  Array result = Array.factory(DataType.STRING, values.getShape());
  IndexIterator ii = result.getIndexIterator();
  values.resetLocalIterator();
  while (values.hasNext()) {
    int ival;
    if (dataType == DataType.ENUM1)
      ival = (int) DataType.unsignedByteToShort(values.nextByte());
    else if (dataType == DataType.ENUM2)
      ival = DataType.unsignedShortToInt(values.nextShort());
    else
      ival = values.nextInt();
    String sval = map.get(ival);
    if (sval == null)
      sval = "Unknown enum value=" + ival;
    ii.setObjectNext(sval);
  }
  return result;
}
 

private CoordinateAxis makeTimeCoordAxisFromReference(NetcdfDataset ds, Variable timeVar, Array vals) {
  Variable refVar = ds.findVariable("reftime");
  if (refVar == null)
    return null;
  double refValue;
  try {
    Array refArray = refVar.read();
    refValue = refArray.getDouble(refArray.getIndex()); // get the first value
  } catch (IOException ioe) {
    return null;
  }
  if (refValue == N3iosp.NC_FILL_DOUBLE)
    return null;

  // construct the values array - make it a double to be safe
  Array dvals = Array.factory(DataType.DOUBLE, vals.getShape());
  IndexIterator diter = dvals.getIndexIterator();
  IndexIterator iiter = vals.getIndexIterator();
  while (iiter.hasNext())
    diter.setDoubleNext(iiter.getDoubleNext() + refValue); // add reftime to each of the values

  String units = ds.findAttValueIgnoreCase(refVar, CDM.UNITS, "seconds since 1970-1-1 00:00:00");
  units = normalize(units);
  String desc = "synthesized time coordinate from reftime, valtimeMINUSreftime";
  CoordinateAxis1D timeCoord = new CoordinateAxis1D(ds, null, "timeCoord", DataType.DOUBLE, "record", units, desc);

  timeCoord.setCachedData(dvals, true);

  parseInfo.format("Created Time Coordinate Axis From Reference = ");
  timeCoord.getNameAndDimensions(parseInfo, true, false);
  parseInfo.format("%n");

  return timeCoord;
}
 

@Nullable
private CoordinateAxis.Builder makeTimeCoordAxisFromReference(Array vals) {
  if (!rootGroup.findVariableLocal("reftime").isPresent())
    return null;
  VariableDS.Builder refVar = (VariableDS.Builder) rootGroup.findVariableLocal("reftime").get();

  double refValue;
  try {
    Array refArray = refVar.orgVar.read();
    refValue = refArray.getDouble(refArray.getIndex()); // get the first value
  } catch (IOException ioe) {
    return null;
  }
  if (refValue == N3iosp.NC_FILL_DOUBLE) // why?
    return null;

  // construct the values array - make it a double to be safe
  Array dvals = Array.factory(DataType.DOUBLE, vals.getShape());
  IndexIterator diter = dvals.getIndexIterator();
  IndexIterator iiter = vals.getIndexIterator();
  while (iiter.hasNext())
    diter.setDoubleNext(iiter.getDoubleNext() + refValue); // add reftime to each of the values

  String name = "timeCoord";
  String units = refVar.getAttributeContainer().findAttributeString(CDM.UNITS, "seconds since 1970-1-1 00:00:00");
  units = normalize(units);
  String desc = "synthesized time coordinate from reftime, valtimeMINUSreftime";
  CoordinateAxis1D.Builder timeCoord =
      CoordinateAxis1D.builder().setName(name).setDataType(DataType.DOUBLE).setParentGroupBuilder(rootGroup)
          .setDimensionsByName("record").setUnits(units).setDesc(desc).setCachedData(dvals, true);

  parseInfo.format("Created Time Coordinate Axis From reftime Variable%n");
  return timeCoord;
}
 

@Override
protected void augmentDataset(CancelTask cancelTask) throws IOException {
  NcMLReaderNew.wrapNcMLresource(datasetBuilder, CoordSystemFactory.resourcesDir + "Zebra.ncml", cancelTask);

  // special time handling
  // the time coord var is created in the NcML
  // set its values = base_time + time_offset(time)
  Dimension timeDim = rootGroup.findDimension("time").orElse(null);
  VariableDS.Builder base_time = (VariableDS.Builder) rootGroup.findVariableLocal("base_time").orElse(null);
  VariableDS.Builder time_offset = (VariableDS.Builder) rootGroup.findVariableLocal("time_offset").orElse(null);
  Variable.Builder time = rootGroup.findVariableLocal("time").orElse(null);
  if ((timeDim == null) || (base_time == null) || (time_offset == null) || (time == null))
    return;

  String units =
      base_time.getAttributeContainer().findAttributeString(CDM.UNITS, "seconds since 1970-01-01 00:00 UTC");
  time.addAttribute(new Attribute(CDM.UNITS, units));

  Array data;
  try {
    double baseValue = base_time.orgVar.readScalarDouble();

    data = time_offset.orgVar.read();
    IndexIterator iter = data.getIndexIterator();
    while (iter.hasNext())
      iter.setDoubleCurrent(iter.getDoubleNext() + baseValue);

  } catch (IOException ioe) {
    parseInfo.format("ZebraConvention failed to create time Coord Axis for file %s err= %s%n",
        datasetBuilder.location, ioe);
    return;
  }

  time.setCachedData(data, true);
}
 

private Array convertDataToChar(Variable newVar, Array oldData) {
  ArrayChar newData = (ArrayChar) Array.factory(DataType.CHAR, newVar.getShape());
  Index ima = newData.getIndex();
  IndexIterator ii = oldData.getIndexIterator();
  while (ii.hasNext()) {
    String s = (String) ii.getObjectNext();
    int[] c = ii.getCurrentCounter();
    for (int i = 0; i < c.length; i++) {
      ima.setDim(i, c[i]);
    }
    newData.setString(ima, s);
  }
  return newData;
}
 

private long findAtt(long start_pos, String want) throws IOException {
  raf.seek(start_pos + 4);

  int natts = raf.readInt();
  for (int i = 0; i < natts; i++) {
    String name = readString();
    if (name.equals(want))
      return raf.getFilePointer();

    int type = raf.readInt();

    if (type == 2) {
      readString();
    } else {
      int nelems = raf.readInt();
      DataType dtype = getDataType(type);
      int[] shape = {nelems};
      Array arr = Array.factory(dtype, shape);
      IndexIterator ii = arr.getIndexIterator();
      int nbytes = 0;
      for (int j = 0; j < nelems; j++)
        nbytes += readAttributeValue(dtype, ii);
      skip(nbytes);
    }
  }

  throw new IllegalArgumentException("no such attribute " + want);
}
 

/**
 * Read data from a top level Variable and send data to a WritableByteChannel.
 *
 * @param v2 Variable
 * @param section wanted section of data of Variable. The section list is a list
 *        of ucar.ma2.Range which define the requested data subset.
 * @param channel WritableByteChannel object - channel that can write bytes.
 * @return the number of bytes written, possibly zero.
 */
public long readToByteChannel11(ucar.nc2.Variable v2, Section section, WritableByteChannel channel)
    throws java.io.IOException {
  Array data = readData(v2, section);
  float[] ftdata = new float[(int) data.getSize()];
  byte[] bytedata = new byte[(int) data.getSize() * 4];
  IndexIterator iter = data.getIndexIterator();
  int i = 0;
  ByteBuffer buffer = ByteBuffer.allocateDirect(bytedata.length);
  while (iter.hasNext()) {
    ftdata[i] = iter.getFloatNext();
    bytedata[i] = new Float(ftdata[i]).byteValue();
    buffer.put(bytedata[i]);
    i++;
  }
  buffer = ByteBuffer.wrap(bytedata);
  // write the bytes to the channel
  int count = channel.write(buffer);
  // check if all bytes where written
  if (buffer.hasRemaining()) {
    // if not all bytes were written, move the unwritten bytes to the beginning and
    // set position just after the last unwritten byte
    buffer.compact();
  } else {
    buffer.clear();
  }
  return (long) count;
}
 

private void readOneRadial(Ray r, Range gateRange, IndexIterator ii) throws IOException {
  if (r == null) {
    for (int i = 0; i < gateRange.length(); i++)
      ii.setFloatNext(Float.NaN);
    return;
  }
  r.readData(volScan.raf, gateRange, ii);
}
 

private void readOneScan(List<Ray> mapScan, Range radialRange, Range gateRange, IndexIterator ii) throws IOException {
  int siz = mapScan.size();
  for (int radialIdx : radialRange) {
    if (radialIdx >= siz)
      readOneRadial(null, gateRange, ii);
    else {
      Ray r = mapScan.get(radialIdx);
      readOneRadial(r, gateRange, ii);
    }
  }
}
 

public void readData0(RandomAccessFile raf, int datatype, Range gateRange, IndexIterator ii) throws IOException {
  long offset = message_offset;
  offset += MESSAGE_HEADER_SIZE; // offset is from "start of digital radar data message header"
  offset += getDataOffset(datatype);
  raf.seek(offset);
  if (logger.isDebugEnabled()) {
    logger.debug("  read recno " + recno + " at offset " + offset + " count= " + getGateCount(datatype));
    logger.debug(
        "   offset: reflect= " + reflect_offset + " velocity= " + velocity_offset + " spWidth= " + spectWidth_offset);
  }

  int dataCount = getGateCount(datatype);
  byte[] data = new byte[dataCount];
  byte[] b4 = new byte[4];
  int j = 0;
  if (datatype == REFLECTIVITY)
    j = 0;
  else if (datatype == VELOCITY_LOW)
    j = 1;
  else if (datatype == SPECTRUM_WIDTH)
    j = 3;

  // raf.readFully(data);

  for (int gateIdx : gateRange) {
    if (gateIdx >= dataCount)
      ii.setByteNext(MISSING_DATA);
    else {
      raf.read(b4);
      data[gateIdx] = b4[j];
      ii.setByteNext(data[gateIdx]);
    }
  }

}
 

protected DapAttribute buildattribute(Attribute cdmattr) throws DapException {
  DapType attrtype = CDMTypeFcns.cdmtype2daptype(cdmattr.getDataType());
  EnumTypedef cdmenum = cdmattr.getEnumType();
  boolean enumfillvalue = (cdmattr.getShortName().equals(FILLVALUE) && cdmenum != null);
  DapEnumeration dapenum = null;

  // We need to handle _FillValue specially if the
  // the variable is enum typed.
  if (enumfillvalue) {
    cdmenum = findMatchingEnum(cdmenum);
    // Make sure the cdm attribute has type enumx
    if (!cdmenum.getBaseType().isEnum())
      throw new DapException("CDM _FillValue attribute type is not enumX");
    // Modify the attr
    cdmattr.setEnumType(cdmenum);
    // Now, map to a DapEnumeration
    dapenum = (DapEnumeration) this.nodemap.get(cdmenum);
    if (dapenum == null)
      throw new DapException("Illegal CDM variable attribute type: " + cdmenum);
    attrtype = dapenum;
  }
  if (attrtype == null)
    throw new DapException("DapFile: illegal CDM variable attribute type: " + cdmattr.getDataType());
  DapAttribute dapattr = (DapAttribute) dmrfactory.newAttribute(cdmattr.getShortName(), attrtype);
  recordNode(cdmattr, dapattr);
  // Transfer the values
  Array values = cdmattr.getValues();
  if (!validatecdmtype(cdmattr.getDataType(), values.getElementType()))
    throw new DapException("Attr type versus attribute data mismatch: " + values.getElementType());
  IndexIterator iter = values.getIndexIterator();
  String[] valuelist = null;
  Object vec = CDMTypeFcns.createVector(cdmattr.getDataType(), values.getSize());
  for (int i = 0; iter.hasNext(); i++) {
    java.lang.reflect.Array.set(vec, i, iter.next());
  }
  valuelist = (String[]) Convert.convert(DapType.STRING, attrtype, vec);
  dapattr.setValues(valuelist);
  return dapattr;
}
 

private float testReadScalar(Variable v) throws IOException {
  if (show)
    System.out.printf(" read %s%n", v.getNameAndDimensions());
  assert (null != v);
  Array a = v.read();
  assert (null != a);
  IndexIterator ii = a.getIndexIterator();
  return ii.getFloatNext();
}
 

@Test
@Category(NeedsCdmUnitTest.class)
public void testLongitudeSubsetWithHorizontalStride() throws IOException, InvalidRangeException {
  String filename = TestDir.cdmUnitTestDir + "tds/ncep/GFS_Global_onedeg_20100913_0000.grib2";
  String gribId = "VAR_0-3-0_L1";

  try (FeatureDatasetCoverage featureDatasetCoverage = CoverageDatasetFactory.open(filename)) {
    CoverageCollection coverageCollection = featureDatasetCoverage.findCoverageDataset(FeatureType.GRID);
    Coverage coverage = coverageCollection.findCoverageByAttribute(Grib.VARIABLE_ID_ATTNAME, gribId);

    final CalendarDate validTime = CalendarDate.parseISOformat(null, "2010-09-21T00:00:00Z");

    HorizCoordSys origHcs = coverage.getCoordSys().getHorizCoordSys();

    // Next, create the subset param and make the request
    SubsetParams params = new SubsetParams();

    // subset Time axis
    params.setTime(validTime);

    // subset across the seam
    final LatLonRect subsetLatLonRequest = new LatLonRect(LatLonPoint.create(-15, -10), 30, 20);
    params.setLatLonBoundingBox(subsetLatLonRequest);

    // set a horizontal stride
    final int stride = 2;
    params.setHorizStride(stride);

    // make subset
    GeoReferencedArray geo = coverage.readData(params);

    // Check that TimeAxis is 1D, has one coordinate, and it's equal to the time we requested
    CoverageCoordAxis timeAxis = geo.getCoordSysForData().getTimeAxis();
    assertThat(timeAxis).isInstanceOf(CoverageCoordAxis1D.class);
    CoverageCoordAxis1D timeAxis1d = (CoverageCoordAxis1D) timeAxis;
    assertThat(timeAxis1d.getNcoords()).isEqualTo(1);
    assertThat(timeAxis1d.makeDate((double) timeAxis1d.getCoordObject(0))).isEqualTo(validTime);

    // make sure the bounding box requested by subset is contained within the
    // horizontal coordinate system of the GeoReferencedArray produced by the
    // subset
    HorizCoordSys subsetHcs = geo.getCoordSysForData().getHorizCoordSys();
    assertThat(subsetLatLonRequest.containedIn(subsetHcs.calcLatLonBoundingBox())).isTrue();

    // make sure resolution of the lat and lon grids of the subset take into account the stride
    // by comparing the resolution
    CoverageCoordAxis1D origLonAxis = origHcs.getXAxis();
    CoverageCoordAxis1D origLatAxis = origHcs.getYAxis();
    CoverageCoordAxis1D subsetLonAxis = subsetHcs.getXAxis();
    CoverageCoordAxis1D subsetLatAxis = subsetHcs.getYAxis();
    final double tol = 0.001;
    assertThat(origLonAxis.getResolution()).isNotWithin(tol).of(subsetLonAxis.getResolution());
    assertThat(origLonAxis.getResolution()).isWithin(tol).of(subsetLonAxis.getResolution() / stride);
    assertThat(origLatAxis.getResolution()).isNotWithin(tol).of(subsetLatAxis.getResolution());
    assertThat(origLatAxis.getResolution()).isWithin(tol).of(subsetLatAxis.getResolution() / stride);

    // check to make sure we get data from both sides of the seam by testing that
    // half of the array isn't empty.
    // slice along longitude in the middle of the array.
    Array geoData = geo.getData();
    int middle = geoData.getShape()[1] / 2;
    Array data = geo.getData().slice(2, middle).reduce();
    // flip the array
    int numValsToSum = 3;
    Array dataFlip = data.flip(0);
    Section sec = Section.builder().appendRange(0, numValsToSum).build();
    IndexIterator dii = data.getIndexIterator();
    IndexIterator diiFlip = dataFlip.getIndexIterator();

    final double initialSumVal = 0;
    double sumData = initialSumVal;
    double sumDataFlip = initialSumVal;
    for (int i = 0; i < numValsToSum - 1; i++) {
      double val = dii.getDoubleNext();
      double valFlip = diiFlip.getDoubleNext();
      // only sum if not missing
      if (!geo.isMissing(val))
        sumData += val;
      if (!geo.isMissing(valFlip))
        sumDataFlip += valFlip;
    }
    assertThat(sumData).isNotEqualTo(initialSumVal);
    assertThat(sumDataFlip).isNotEqualTo(initialSumVal);
  }
}
 

private Variable.Builder copyVariable(Group.Builder parent, Variable oldVar) throws IOException {
  Variable.Builder vb;
  DataType newType = oldVar.getDataType();
  String dimNames = Dimensions.makeDimensionsString(oldVar.getDimensions());

  if (newType == DataType.STRUCTURE) {
    Structure oldStruct = (Structure) oldVar;
    Structure.Builder sb = Structure.builder().setName(oldVar.getShortName());
    for (Variable nested : oldStruct.getVariables()) {
      sb.addMemberVariable(copyVariable(parent, nested));
    }
    vb = sb;
  } else {
    vb = Variable.builder().setName(oldVar.getShortName()).setDataType(newType);
    if (!extended && newType == DataType.STRING) {
      // find maximum length
      Array data = oldVar.read();
      IndexIterator ii = data.getIndexIterator();
      int max_len = 0;
      while (ii.hasNext()) {
        String s = (String) ii.getObjectNext();
        max_len = Math.max(max_len, s.length());
      }

      // add last dimension
      String strlenDimName = oldVar.getShortName() + "_strlen";
      parent.addDimension(Dimension.builder(strlenDimName, max_len).setIsShared(false).build());

      newType = DataType.CHAR;
      vb.setDataType(DataType.CHAR);
      dimNames += " " + strlenDimName;
    }
  }
  vb.setParentGroupBuilder(parent).setDimensionsByName(dimNames);

  if (newType.isEnum()) {
    EnumTypedef en = oldVar.getEnumTypedef();
    vb.setEnumTypeName(en.getShortName());
  }

  // attributes
  for (Attribute att : oldVar.attributes()) {
    vb.addAttribute(convertAttribute(att));
    if (debug) {
      System.out.println("add varAtt= " + att);
    }
  }

  return vb;
}
 

private Element writeAxis(CoverageCoordAxis axis) {
  Element varElem = new Element("axis");
  varElem.setAttribute("name", axis.getName());
  varElem.setAttribute("shape", Arrays.toString(axis.getShape()));

  DataType dt = axis.getDataType();
  varElem.setAttribute("type", dt.toString());

  AxisType axisType = axis.getAxisType();
  if (null != axisType)
    varElem.setAttribute("axisType", axisType.toString());

  if (axis.getDependsOn() != null && !axis.getDependsOn().trim().isEmpty())
    varElem.setAttribute("dependsOn", axis.getDependsOn().trim());

  // attributes
  for (Attribute att : axis.getAttributes()) {
    varElem.addContent(ncmlWriter.makeAttributeElement(att));
  }

  /*
   * f.format("%s  npts: %d [%f,%f] spacing=%s", indent, ncoords, startValue, endValue, spacing);
   * if (getResolution() != 0.0)
   * f.format(" resolution=%f", resolution);
   * f.format(" %s :", getDependenceType());
   * for (String s : dependsOn)
   */

  Element values = new Element("values");
  if (!axis.isRegular()) {
    Array array = axis.getCoordsAsArray();
    boolean isRealType = (array.getDataType() == DataType.DOUBLE) || (array.getDataType() == DataType.FLOAT);
    IndexIterator iter = array.getIndexIterator();

    StringBuilder buff = new StringBuilder();
    buff.append(isRealType ? iter.getDoubleNext() : iter.getIntNext());

    while (iter.hasNext()) {
      buff.append(" ");
      buff.append(isRealType ? iter.getDoubleNext() : iter.getIntNext());
    }

    values.setText(buff.toString());
  }

  values.setAttribute("spacing", axis.getSpacing().toString());
  values.setAttribute("npts", Long.toString(axis.getNcoords()));
  values.setAttribute("start", Double.toString(axis.getStartValue()));
  values.setAttribute("end", Double.toString(axis.getEndValue()));
  if (axis.getResolution() != 0.0)
    values.setAttribute("resolution", Double.toString(axis.getResolution()));

  varElem.addContent(values);
  return varElem;
}
 

@Nullable
private CoordinateAxis.Builder makeZCoordAxis(String axisName, String dimName) {
  Optional<Dimension> dimOpt = rootGroup.findDimension(dimName);
  if (!dimOpt.isPresent()) {
    return null;
  }
  Dimension dim = dimOpt.get();

  String fromWhere = axisName.endsWith("stag") ? "ZNW" : "ZNU";

  CoordinateAxis.Builder v =
      CoordinateAxis1D.builder().setName(axisName).setDataType(DataType.DOUBLE).setParentGroupBuilder(rootGroup)
          .setDimensionsByName(dim.getShortName()).setUnits("").setDesc("eta values from variable " + fromWhere);
  v.addAttribute(new Attribute(CF.POSITIVE, CF.POSITIVE_DOWN)); // eta coordinate is 1.0 at bottom, 0 at top
  v.setAxisType(AxisType.GeoZ);
  v.addAttribute(new Attribute(_Coordinate.AxisType, "GeoZ"));
  if (!axisName.equals(dim.getShortName()))
    v.addAttribute(new Attribute(_Coordinate.AliasForDimension, dim.getShortName()));

  // create eta values from file variables: ZNU, ZNW
  // But they are a function of time though the values are the same in the sample file
  // NOTE: Use first time sample assuming all are the same!!
  Optional<Variable.Builder<?>> etaVarOpt = rootGroup.findVariableLocal(fromWhere);
  if (!etaVarOpt.isPresent()) {
    return makeFakeCoordAxis(axisName, dim);
  } else {
    VariableDS.Builder<?> etaVarDS = (VariableDS.Builder<?>) etaVarOpt.get();
    Variable etaVar = etaVarDS.orgVar;
    int n = etaVar.getShape(1); // number of eta levels
    int[] origin = {0, 0};
    int[] shape = {1, n};
    try {
      Array array = etaVar.read(origin, shape);// read first time slice
      ArrayDouble.D1 newArray = new ArrayDouble.D1(n);
      IndexIterator it = array.getIndexIterator();
      int count = 0;
      while (it.hasNext()) {
        double d = it.getDoubleNext();
        newArray.set(count++, d);
      }
      v.setCachedData(newArray, true);
    } catch (Exception e) {
      e.printStackTrace();
    } // ADD: error?

    return v;
  }
}
 

@Override
public Array convert(Array in, boolean convertUnsigned, boolean applyScaleOffset, boolean convertMissing) {
  if (!in.getDataType().isNumeric() || (!convertUnsigned && !applyScaleOffset && !convertMissing)) {
    return in; // Nothing to do!
  }

  if (getSignedness() == Signedness.SIGNED) {
    convertUnsigned = false;
  }
  if (!hasScaleOffset()) {
    applyScaleOffset = false;
  }

  DataType outType = origDataType;
  if (convertUnsigned) {
    outType = getUnsignedConversionType();
  }
  if (applyScaleOffset) {
    outType = getScaledOffsetType();
  }

  if (outType != DataType.FLOAT && outType != DataType.DOUBLE) {
    convertMissing = false;
  }

  Array out = Array.factory(outType, in.getShape());
  IndexIterator iterIn = in.getIndexIterator();
  IndexIterator iterOut = out.getIndexIterator();

  while (iterIn.hasNext()) {
    Number value = (Number) iterIn.getObjectNext();

    if (convertUnsigned) {
      value = convertUnsigned(value);
    }
    if (applyScaleOffset) {
      value = applyScaleOffset(value);
    }
    if (convertMissing) {
      value = convertMissing(value);
    }

    iterOut.setObjectNext(value);
  }

  return out;
}
 

protected void copyTo1DJavaArray(IndexIterator indexIterator, Object o) {
  throw new UnsupportedOperationException();
}
 

VarIter(Coverage cov, GeoReferencedArray array, IndexIterator dataIter) {
  this.cov = cov;
  this.geoA = array;
  this.dataIter = dataIter;
}