code: @Override
      public int iamin(INDArray arr) {
          if (arr.isSparse()) {
              return Nd4j.getSparseBlasWrapper().level1().iamin(arr);
          } else {
              throw new UnsupportedOperationException();
          }
      }
docs: finds the element of a vector that has the minimum absolute value.
  
  @param arr
  @return