Java DoubleMatrix2D.forEachNonZero方法代码示例

import cern.colt.matrix.DoubleMatrix2D; //导入方法依赖的package包/类
public static DoubleMatrix1D logMult(DoubleMatrix2D M, DoubleMatrix1D y, DoubleMatrix1D z, double alpha, double beta, boolean transposeA) {
        // z = alpha * A * y + beta*z
        double lalpha = 0;
        if (alpha != 1)
            lalpha = Math.log(alpha);
        if (beta != 0) {
            if (beta != 1) {
                double lbeta = Math.log(beta);
                for (int i = 0; i < z.size(); z.set(i,z.get(i)+lbeta),i++);
            }
        } else {
            z.assign(RobustMath.LOG0);
        }
        // in log domain this becomes: 
        logMult.M = M;
        logMult.z = z;
        logMult.lalpha = lalpha;
        logMult.transposeA = transposeA;
        logMult.y = y;
        logMult.cnt=0;
        M.forEachNonZero(logMult);
//      System.out.println("Matrix "+M.size()+" "+M.columns()+ " "+logMult.cnt);
        return z;
    }
 

import cern.colt.matrix.DoubleMatrix2D; //导入方法依赖的package包/类
/**
 * Replaces all cell values of the receiver with the values of another matrix.
 * Both matrices must have the same number of rows and columns.
 * If both matrices share the same cells (as is the case if they are views derived from the same matrix) and intersect in an ambiguous way, then replaces <i>as if</i> using an intermediate auxiliary deep copy of <tt>other</tt>.
 *
 * @param     source   the source matrix to copy from (may be identical to the receiver).
 * @return <tt>this</tt> (for convenience only).
 * @throws	IllegalArgumentException if <tt>columns() != source.columns() || rows() != source.rows()</tt>
 */
public DoubleMatrix2D assign(DoubleMatrix2D source) {
	// overriden for performance only
	if (source==this) return this; // nothing to do
	checkShape(source);

	if (source instanceof TridiagonalDoubleMatrix2D) {
		// quickest
		TridiagonalDoubleMatrix2D other = (TridiagonalDoubleMatrix2D) source;
		
		System.arraycopy(other.values, 0, this.values, 0, this.values.length);
		System.arraycopy(other.dims, 0, this.dims, 0, this.dims.length);
		return this;
	}

	if (source instanceof RCDoubleMatrix2D || source instanceof SparseDoubleMatrix2D) {
		assign(0);
		source.forEachNonZero(
			new cern.colt.function.IntIntDoubleFunction() {
				public double apply(int i, int j, double value) {
					setQuick(i,j,value);
					return value;
				}
			}
		);	
		return this;
	}
	
	return super.assign(source);
}
 

import cern.colt.matrix.DoubleMatrix2D; //导入方法依赖的package包/类
/**
 * Replaces all cell values of the receiver with the values of another matrix.
 * Both matrices must have the same number of rows and columns.
 * If both matrices share the same cells (as is the case if they are views derived from the same matrix) and intersect in an ambiguous way, then replaces <i>as if</i> using an intermediate auxiliary deep copy of <tt>other</tt>.
 *
 * @param     source   the source matrix to copy from (may be identical to the receiver).
 * @return <tt>this</tt> (for convenience only).
 * @throws	IllegalArgumentException if <tt>columns() != source.columns() || rows() != source.rows()</tt>
 */
public DoubleMatrix2D assign(DoubleMatrix2D source) {
	if (source==this) return this; // nothing to do
	checkShape(source);
	// overriden for performance only
	if (! (source instanceof RCDoubleMatrix2D)) {
		//return super.assign(source);

		assign(0);
		source.forEachNonZero(
			new cern.colt.function.IntIntDoubleFunction() {
				public double apply(int i, int j, double value) {
					setQuick(i,j,value);
					return value;
				}
			}
		);
		/*
		indexes.clear();
		values.clear();
		int nonZeros=0;
		for (int row=0; row<rows; row++) {
			starts[row]=nonZeros;
			for (int column=0; column<columns; column++) {
				double v = source.getQuick(row,column);
				if (v!=0) {
					values.add(v);
					indexes.add(column);
					nonZeros++;
				}
			}
		}
		starts[rows]=nonZeros;
		*/
		return this;
	}

	// even quicker
	RCDoubleMatrix2D other = (RCDoubleMatrix2D) source;
	
	System.arraycopy(other.starts, 0, this.starts, 0, this.starts.length);
	int s = other.indexes.size();
	this.indexes.setSize(s);
	this.values.setSize(s);
	this.indexes.replaceFromToWithFrom(0,s-1,other.indexes,0);
	this.values.replaceFromToWithFrom(0,s-1,other.values,0);
	
	return this;
}