isimaginary.java

JAVA 数学程序库 提供常规的数值计算程序包

package jmathlib.toolbox.jmathlib.matrix;

import jmathlib.core.tokens.Token;
import jmathlib.core.tokens.OperandToken;
import jmathlib.core.tokens.numbertokens.DoubleNumberToken;
import jmathlib.core.functions.ExternalFunction;

/**An external function that return 1.0 is real elements of the argument are zero  */
public class isimaginary extends ExternalFunction
{
	/**return a  matrix 
	* @param operands[0] = matrix 
	* @return 1.0 if all elements of the argument are nonzero  */
	public OperandToken evaluate(Token[] operands)
	{

		// two operands (e.g. not(A) )
        if (getNArgIn(operands) != 1)
			throwMathLibException("isimaginary: number of arguments != 1");
        
        if (!(operands[0] instanceof DoubleNumberToken))
            throwMathLibException("isimaginary: works on numbers only");


		// get data from arguments
        double[][] a_r = ((DoubleNumberToken)operands[0]).getReValues();
		int a_dy       = a_r.length;
        int a_dx       = a_r[0].length;	
        boolean imagB  = true;
	
		for (int xi=0; xi<a_dx ; xi++)
		{
			for (int yi=0; yi<a_dy ; yi++)
			{
				if ( a_r[yi][xi] != 0.0)
                    imagB = false;
			}
		}	
        
		if (imagB)
		    return new DoubleNumberToken(1.0);		
		else
		    return new DoubleNumberToken(0.0);        

        
	} // end eval
}

/*
@GROUP
matrix
@SYNTAX
answer = isimaginary(matrix)
@DOC
Returns 1 if any of the elements of the supplied matrix are not zero.
@NOTES
@EXAMPLES
any([0,0;0,0]) = 0
any([1,0;0,0]) = 1
@SEE
any
*/