code: public static final DoubleMatrix1D scalarMult(DoubleMatrix1D v1, double c){
  		DoubleMatrix1D ret = DoubleFactory1D.dense.make(v1.size());
  		for(int i=0; i<ret.size(); i++){
  			ret.setQuick(i, c * v1.getQuick(i));
  		}
  
  		return ret;
  	}
docs: Returns v = c * v1.
  Useful in avoiding the need of the copy() in the colt api.