throw new IllegalArgumentException("invalid parameter col1 = " + col1);
throw new IllegalArgumentException("invalid parameter col2 = " + col2);
    public void swapCols(int col1, int col2) {	int totalCols = this.getCols();	if((col1 < 0)||(col1 >= totalCols)) 	   throw new IllegalArgumentException("invalid parameter col1 = " + col1);	if((col2 < 0)||(col2 >= totalCols)) 	   throw new IllegalArgumentException("invalid parameter col1 = " + col1);	int totalRows = this.getRows();	double swap_r, swap_i;	for(int i=0; i<totalRows; i++) {	    swap_r = this.internalMatrixReal[i][col1];	    this.internalMatrixReal[i][col1] = this.internalMatrixReal[i][col2];	    this.internalMatrixReal[i][col2] = swap_r;	    swap_i = this.internalMatrixImag[i][col1];	    this.internalMatrixImag[i][col1] = this.internalMatrixImag[i][col2];	    this.internalMatrixImag[i][col2] = swap_r;	}    }