Java DataSource.getColumnCount方法代码示例

import de.erichseifert.gral.data.DataSource; //导入方法依赖的package包/类
/**
 * Sets the mapping of data source columns to axis names. The column index
 * is taken from the order of the axis names, i.e. the first column of
 * {@code source} will be mapped to first element of {@code axisNames}.
 * Axis names with value {@code null} will be ignored.
 * @param source Data source.
 * @param axisNames Sequence of axis names in the order of the columns.
 */
public void setMapping(DataSource source, String... axisNames) {
	if (!contains(source)) {
		throw new IllegalArgumentException(
			"Data source does not exist in plot."); //$NON-NLS-1$
	}
	if (axisNames.length > source.getColumnCount()) {
		throw new IllegalArgumentException(MessageFormat.format(
			"Data source only has {0,number,integer} column, {1,number,integer} values given.", //$NON-NLS-1$
			source.getColumnCount(), axisNames.length));
	}
	Map<Integer, String> columnToAxisMapping = new HashMap<>();
	for (int col = 0; col < axisNames.length; col++) {
		String axisName = axisNames[col];
		if (axisName != null) {
			columnToAxisMapping.put(col, axisName);
		}
	}
	columnToAxisMappingByDataSource.put(source, columnToAxisMapping);
	invalidateAxisExtrema();
}
 

import de.erichseifert.gral.data.DataSource; //导入方法依赖的package包/类
/**
 * Stores the specified data source.
 * @param data DataSource to be stored.
 * @param output OutputStream to be written to.
 * @throws IOException if writing the data failed
 */
public void write(DataSource data, OutputStream output) throws IOException {
	Character separator = getSetting(SEPARATOR_CHAR);
	OutputStreamWriter writer = new OutputStreamWriter(output);

	int i = 0;
	int colCount = data.getColumnCount();
	for (Comparable<?> cell : data) {
		writer.write(String.valueOf(cell));

		int col = i % colCount;
		if (col < colCount - 1) {
			writer.write(separator);
		} else {
			writer.write("\r\n"); //$NON-NLS-1$
		}
		i++;
	}

	writer.close();
}
 

import de.erichseifert.gral.data.DataSource; //导入方法依赖的package包/类
/**
 * Extracts statistics from the columns of an data source that are commonly
 * used for box-and-whisker plots. The result is a new data source
 * containing <i>column index</i>, <i>median</i>, <i>mininum</i>, <i>first
 * quartile</i>, <i>third quartile</i>, and <i>maximum</i> for each column.
 * @param data Original data source
 * @return New data source with (columnIndex, median, min, quartile1,
 *         quartile3, max)
 */
@SuppressWarnings("unchecked")
public static DataSource createBoxData(DataSource data) {
	if (data == null) {
		throw new NullPointerException(
			"Cannot extract statistics from null data source.");
	}

	DataTable stats = new DataTable(Integer.class, Double.class,
		Double.class, Double.class, Double.class, Double.class);

	// Generate statistical values for each column
	for (int c = 0; c < data.getColumnCount(); c++) {
		Column col = data.getColumn(c);
		if (!col.isNumeric()) {
			continue;
		}
		stats.add(
			c + 1,
			col.getStatistics(Statistics.MEDIAN),
			col.getStatistics(Statistics.MIN),
			col.getStatistics(Statistics.QUARTILE_1),
			col.getStatistics(Statistics.QUARTILE_3),
			col.getStatistics(Statistics.MAX)
		);
	}
	return stats;
}
 

import de.erichseifert.gral.data.DataSource; //导入方法依赖的package包/类
private List<Class<? extends Comparable<?>>> getColumnTypesFor(DataSource data) {
	List<Class<? extends Comparable<?>>> columnTypes = new LinkedList<>();
	for (int colIndex = 0; colIndex < data.getColumnCount(); colIndex++) {
		Column<?> column = data.getColumn(colIndex);
		if (column.isNumeric()) {
			columnTypes.add(Double.class);
			columnTypes.add(Double.class);
			columnTypes.add(Boolean.class);
		} else {
			columnTypes.add(column.getType());
		}
	}
	return columnTypes;
}
 

import de.erichseifert.gral.data.DataSource; //导入方法依赖的package包/类
/**
 * Takes a matrix of values and creates a new data source that stores the
 * values in (x, y, value) format.
 * @param data Original data source with values in each cell.
 * @return New data source with (x, y, value) columns
 */
@SuppressWarnings("unchecked")
public static DataSource createRasterData(DataSource data) {
	if (data == null) {
		throw new NullPointerException("Cannot convert null data source.");
	}

	DataTable coordsValueData =
		new DataTable(Double.class, Double.class, Double.class);

	// Generate pixel data with (x, y, value)
	double min = ((Number) data.getRowStatistics(Statistics.MIN).
			getColumnStatistics(Statistics.MIN).get(0, 0)).doubleValue();
	double max = ((Number) data.getRowStatistics(Statistics.MAX).
			getColumnStatistics(Statistics.MAX).get(0, 0)).doubleValue();
	double range = max - min;
	int i = 0;
	for (Comparable<?> cell : data) {
		int x =  i%data.getColumnCount();
		int y = -i/data.getColumnCount();
		double v = Double.NaN;
		if (cell instanceof Number) {
			Number numericCell = (Number) cell;
			v = (numericCell.doubleValue() - min) / range;
		}
		coordsValueData.add((double) x, (double) y, v);
		i++;
	}
	return coordsValueData;
}
 

import de.erichseifert.gral.data.DataSource; //导入方法依赖的package包/类
/**
 * Stores the specified data source.
 * @param data DataSource to be stored.
 * @param output OutputStream to be written to.
 * @throws IOException if writing the data failed
 */
public void write(DataSource data, OutputStream output) throws IOException {
	int w = data.getColumnCount();
	int h = data.getRowCount();

	double factor = this.<Number>getSetting("factor").doubleValue(); //$NON-NLS-1$
	double offset = this.<Number>getSetting("offset").doubleValue(); //$NON-NLS-1$

	byte[] pixelData = new byte[w*h];
	int pos = 0;
	for (int y = 0; y < h; y++) {
		for (int x = 0; x < w; x++) {
			Comparable<?> cell = data.get(x, y);
			if (!(cell instanceof Number)) {
				continue;
			}
			Number numericCell = (Number) cell;
			double value = numericCell.doubleValue()*factor + offset;
			byte v = (byte) Math.round(MathUtils.limit(value, 0.0, 255.0));
			pixelData[pos++] = v;
		}
	}

       BufferedImage image =
       	new BufferedImage(w, h, BufferedImage.TYPE_BYTE_GRAY);
       image.getRaster().setDataElements(0, 0, w, h, pixelData);

       Iterator<javax.imageio.ImageWriter> writers =
       	ImageIO.getImageWritersByMIMEType(getMimeType());
       try {
       	javax.imageio.ImageWriter writer = writers.next();
       	writer.setOutput(ImageIO.createImageOutputStream(output));
       	writer.write(image);
       } catch (NoSuchElementException e) {
       	throw new IOException(MessageFormat.format(
       			"No writer found for MIME type {0}.", getMimeType())); //$NON-NLS-1$
       }
}
 

import de.erichseifert.gral.data.DataSource; //导入方法依赖的package包/类
/**
 * Returns the mapping of data source columns to axis names. The elements
 * of returned array equal the column indexes, i.e. the first element (axis
 * name) matches the first column of {@code source}. If no mapping exists
 * {@code null} will be stored in the array.
 * @param source Data source.
 * @return Array containing axis names in the order of the columns,
 *         or {@code null} if no mapping exists for the column.
 */
public String[] getMapping(DataSource source) {
	String[] mapping = new String[source.getColumnCount()];
	for (int col = 0; col < mapping.length; col++) {
		mapping[col] = getMapping(source, col);
	}
	return mapping;
}