code: static boolean isDense(Format format) {
          switch (format) {
              case DENSE_TEXT:
              case SVDLIBC_DENSE_TEXT:
              case SVDLIBC_DENSE_BINARY:
                  return true;
              case MATLAB_SPARSE:
              case SVDLIBC_SPARSE_TEXT:
              case SVDLIBC_SPARSE_BINARY:
                  return false;
              default:
                  // We should never get here unless another format is added and
                  // this method is never updated
                  assert false : format;
          }
          return true;
      }
docs: Returns {@code true} if the format is likely to produce a dense matrix.
  Due to the actual matrix contents being unknown, the return value is
  actual a best-effort guess.
  
  @param format the format of a matrix on disk
  @return {@code true} if the matrix is likely to be a dense matrix