Java Code Examples for java.io.RandomAccessFile#readFloat()

/**
 * Read big header
 *
 * @param br The randomAccessFile
 * @param isSequential If is sequential
 * @return The big header
 * @throws IOException
 */
public BigHeader readBigHeader(RandomAccessFile br, boolean isSequential) throws IOException {
    BigHeader bh = new BigHeader();
    if (isSequential) {
        br.skipBytes(4);
    }
    byte[] bytes = new byte[80];
    int i, j;
    for (i = 0; i < 20; i++) {
        for (j = 0; j < 50; j++) {
            bh.bhi[j][i] = br.readInt();
        }
    }
    for (i = 0; i < 20; i++) {
        for (j = 0; j < 20; j++) {
            bh.bhr[j][i] = br.readFloat();
        }
    }
    for (i = 0; i < 20; i++) {
        for (j = 0; j < 50; j++) {
            br.read(bytes);
            bh.bhic[j][i] = new String(bytes).trim();
        }
    }
    for (i = 0; i < 20; i++) {
        for (j = 0; j < 20; j++) {
            br.read(bytes);
            bh.bhrc[j][i] = new String(bytes).trim();
        }
    }

    if (isSequential) {
        br.skipBytes(4);
    }

    return bh;
}
 

/**
 * Read sub header
 *
 * @param br The randomAccessFile
 * @param isSequential If if sequential
 * @return The sub header
 * @throws IOException
 */
public SubHeader readSubHeader(RandomAccessFile br, boolean isSequential) throws IOException {
    SubHeader sh = new SubHeader();
    byte[] bytes = new byte[4];
    int i;
    if (isSequential) {
        br.skipBytes(4);
    }

    sh.ndim = br.readInt();
    for (i = 0; i < 4; i++) {
        sh.start_index[i] = br.readInt();
    }
    for (i = 0; i < 4; i++) {
        sh.end_index[i] = br.readInt();
    }
    sh.xtime = br.readFloat();
    br.read(bytes);
    sh.staggering = new String(bytes).trim();
    br.read(bytes);
    sh.ordering = new String(bytes).trim();
    bytes = new byte[24];
    br.read(bytes);
    sh.current_date = new String(bytes).trim();
    bytes = new byte[9];
    br.read(bytes);
    sh.name = new String(bytes).trim();
    bytes = new byte[25];
    br.read(bytes);
    sh.unit = new String(bytes).trim();
    bytes = new byte[46];
    br.read(bytes);
    sh.description = new String(bytes).trim();

    if (isSequential) {
        br.skipBytes(4);
    }

    return sh;
}
 

/**
 * Read array data of the variable
 *
 * @param varName Variable name
 * @param origin The origin array
 * @param size The size array
 * @param stride The stride array
 * @return Array data
 */
@Override
public Array read(String varName, int[] origin, int[] size, int[] stride) {
    try {
        Variable var = this.getVariable(varName);
        int timeIdx = (int)var.findAttribute("time_index").getNumericValue();
        int particleNum = _parameters.get(timeIdx).get(0);
        int pollutantNum = _parameters.get(timeIdx).get(1);
        int pos = _parameters.get(timeIdx).get(2);
        Array r = Array.factory(var.getDataType(), new int[]{particleNum});

        RandomAccessFile br = new RandomAccessFile(this.getFileName(), "r");
        int i, j;
        float lon, lat, alt;

        br.seek(pos);
        br.skipBytes(28);
        for (i = 0; i < particleNum; i++) {
            br.skipBytes(8);
            for (j = 0; j < pollutantNum; j++) {
                br.skipBytes(4);
            }
            br.skipBytes(8);
            lat = br.readFloat();
            lon = br.readFloat();
            alt = br.readFloat();

            if (varName.startsWith("lon"))
                r.setFloat(i, lon);
            else if (varName.startsWith("lat"))
                r.setFloat(i, lat);
            else
                r.setFloat(i, alt);

            br.skipBytes(40);
        }

        return r;
    } catch (IOException e) {
        return null;
    }
}
 

/**
 * Read data frame
 *
 * @param timeIdx Time index
 * @return Data frame
 */
public DataFrame readDataFrame(int timeIdx) {
    try {
        int particleNum = _parameters.get(timeIdx).get(0);
        int pollutantNum = _parameters.get(timeIdx).get(1);
        int pos = _parameters.get(timeIdx).get(2);
        List<Array> data = new ArrayList<>();
        ColumnIndex columns = new ColumnIndex();
        for (Variable var : this.variables) {
            if ((int)var.findAttribute("time_index").getNumericValue() == timeIdx) {
                columns.add(new Column(var.getName(), var.getDataType()));
                data.add(Array.factory(var.getDataType(), new int[]{particleNum}));
            }
        }

        RandomAccessFile br = new RandomAccessFile(this.getFileName(), "r");
        int i, j;
        float lon, lat, alt;

        br.seek(pos);
        br.skipBytes(28);
        for (i = 0; i < particleNum; i++) {
            br.skipBytes(8);
            for (j = 0; j < pollutantNum; j++) {
                br.skipBytes(4);
            }
            br.skipBytes(8);
            lat = br.readFloat();
            lon = br.readFloat();
            alt = br.readFloat();

            data.get(0).setFloat(i, lat);
            data.get(1).setFloat(i, lon);
            data.get(2).setFloat(i, alt);

            br.skipBytes(40);
        }

        Index index = Index.factory(particleNum);
        DataFrame df = new DataFrame(data, index, columns);
        return df;
    } catch (IOException e) {
        return null;
    }
}
 

@Override
public StationData getStationData(int timeIdx, String varName, int levelIdx) {
    try {
        StationData stationData = new StationData();
        List<String> stations = new ArrayList<String>();
        int particleNum = _parameters.get(timeIdx).get(0);
        int pollutantNum = _parameters.get(timeIdx).get(1);
        int pos = _parameters.get(timeIdx).get(2);
        double[][] discreteData = new double[particleNum][3];

        RandomAccessFile br = new RandomAccessFile(this.getFileName(), "r");
        byte[] aBytes;
        int i, j;
        float lon, lat, alt;
        float minX, maxX, minY, maxY;
        minX = 0;
        maxX = 0;
        minY = 0;
        maxY = 0;

        br.seek(pos);
        br.skipBytes(28);
        for (i = 0; i < particleNum; i++) {
            br.skipBytes(8);
            for (j = 0; j < pollutantNum; j++) {
                br.skipBytes(4);
            }
            br.skipBytes(8);
            lat = br.readFloat();
            lon = br.readFloat();
            alt = br.readFloat();

            discreteData[i][0] = lon;
            discreteData[i][1] = lat;
            discreteData[i][2] = alt;
            stations.add("P" + String.valueOf(i + 1));

            br.skipBytes(40);

            if (i == 0) {
                minX = lon;
                maxX = minX;
                minY = lat;
                maxY = minY;
            } else {
                if (minX > lon) {
                    minX = lon;
                } else if (maxX < lon) {
                    maxX = lon;
                }
                if (minY > lat) {
                    minY = lat;
                } else if (maxY < lat) {
                    maxY = lat;
                }
            }
        }
        Extent dataExtent = new Extent();
        dataExtent.minX = minX;
        dataExtent.maxX = maxX;
        dataExtent.minY = minY;
        dataExtent.maxY = maxY;

        br.close();

        stationData.data = discreteData;
        stationData.dataExtent = dataExtent;
        stationData.stations = stations;

        return stationData;
    } catch (IOException ex) {
        Logger.getLogger(HYSPLITPartDataInfo.class.getName()).log(Level.SEVERE, null, ex);
        return null;
    }
}