AbstractVector implements Vector { @Override public double zSum() { double result = 0.0; Iterator<Element> iter = iterateNonZero(); while (iter.hasNext()) { result += iter.next().get(); } return result; } protected  AbstractVector(int size); @Override double aggregate(DoubleDoubleFunction aggregator, DoubleFunction map); @Override double aggregate(Vector other, DoubleDoubleFunction aggregator, DoubleDoubleFunction combiner); @Override Vector viewPart(int offset, int length); @Override Vector clone(); @Override Vector divide(double x); @Override double dot(Vector x); double dotSelf(); @Override double get(int index); @Override Element getElement(int index); @Override Vector minus(Vector that); @Override Vector normalize(); @Override Vector normalize(double power); @Override Vector logNormalize(); @Override Vector logNormalize(double power); Vector logNormalize(double power, double normLength); @Override double norm(double power); @Override double getLengthSquared(); @Override double getDistanceSquared(Vector v); @Override double maxValue(); @Override int maxValueIndex(); @Override double minValue(); @Override int minValueIndex(); @Override Vector plus(double x); @Override Vector plus(Vector x); @Override void set(int index, double value); @Override Vector times(double x); @Override Vector times(Vector x); @Override double zSum(); @Override Vector assign(double value); @Override Vector assign(double[] values); @Override Vector assign(Vector other); @Override Vector assign(DoubleDoubleFunction f, double y); @Override Vector assign(DoubleFunction function); @Override Vector assign(Vector other, DoubleDoubleFunction function); @Override Matrix cross(Vector other); @Override final int size(); @Override String asFormatString(); @Override int hashCode(); @Override boolean equals(Object o); @Override String toString(); String toString(String[] dictionary);  }
@Test public void testZSum() { double expected = 0; for (double value : values) { expected += value; } assertEquals("wrong zSum", expected, test.zSum(), EPSILON); }