RealVector { public double getL1Norm() { double norm = 0; Iterator<Entry> it = iterator(); while (it.hasNext()) { final Entry e = it.next(); norm += FastMath.abs(e.getValue()); } return norm; }  abstract int getDimension(); abstract double getEntry(int index); abstract void setEntry(int index, double value); void addToEntry(int index, double increment); abstract RealVector append(RealVector v); abstract RealVector append(double d); abstract RealVector getSubVector(int index, int n); abstract void setSubVector(int index, RealVector v); abstract boolean isNaN(); abstract boolean isInfinite(); RealVector add(RealVector v); RealVector subtract(RealVector v); RealVector mapAdd(double d); RealVector mapAddToSelf(double d); abstract RealVector copy(); double dotProduct(RealVector v); double cosine(RealVector v); abstract RealVector ebeDivide(RealVector v); abstract RealVector ebeMultiply(RealVector v); double getDistance(RealVector v); double getNorm(); double getL1Norm(); double getLInfNorm(); double getL1Distance(RealVector v); double getLInfDistance(RealVector v); int getMinIndex(); double getMinValue(); int getMaxIndex(); double getMaxValue(); RealVector mapMultiply(double d); RealVector mapMultiplyToSelf(double d); RealVector mapSubtract(double d); RealVector mapSubtractToSelf(double d); RealVector mapDivide(double d); RealVector mapDivideToSelf(double d); RealMatrix outerProduct(RealVector v); RealVector projection(final RealVector v); void set(double value); double[] toArray(); RealVector unitVector(); void unitize(); Iterator<Entry> sparseIterator(); Iterator<Entry> iterator(); RealVector map(UnivariateFunction function); RealVector mapToSelf(UnivariateFunction function); RealVector combine(double a, double b, RealVector y); RealVector combineToSelf(double a, double b, RealVector y); double walkInDefaultOrder(final RealVectorPreservingVisitor visitor); double walkInDefaultOrder(final RealVectorPreservingVisitor visitor,
                                     final int start, final int end); double walkInOptimizedOrder(final RealVectorPreservingVisitor visitor); double walkInOptimizedOrder(final RealVectorPreservingVisitor visitor,
                                       final int start, final int end); double walkInDefaultOrder(final RealVectorChangingVisitor visitor); double walkInDefaultOrder(final RealVectorChangingVisitor visitor,
                              final int start, final int end); double walkInOptimizedOrder(final RealVectorChangingVisitor visitor); double walkInOptimizedOrder(final RealVectorChangingVisitor visitor,
                                       final int start, final int end); @Override boolean equals(Object other); @Override int hashCode(); static RealVector unmodifiableRealVector(final RealVector v);  }
@Test @Ignore("Abstract class RealVector does not implement getL1Norm()") @Override public void testGetL1Norm() { }