code: private void validate() {
          if (isDense() && isPattern())
              throw new IllegalArgumentException(
                      "Matrix cannot be dense with pattern storage");
          if (isReal() && isHermitian())
              throw new IllegalArgumentException(
                      "Data cannot be real with hermitian symmetry");
          if (!isComplex() && isHermitian())
              throw new IllegalArgumentException(
                      "Data must be complex with hermitian symmetry");
          if (isPattern() && isSkewSymmetric())
              throw new IllegalArgumentException(
                      "Storage cannot be pattern and skew symmetrical");
      }
docs: Validates the representation