*/
  protected long edgeCount() {
    long degreeSum = 0L;
    for (N node : nodes()) {
      degreeSum += degree(node);
    }
    // According to the degree sum formula, this is equal to twice the number of edges.
    checkState((degreeSum & 1) == 0);
    return degreeSum >>> 1;
  }

  /**
   * An implementation of {@link BaseGraph#edges()} defined in terms of {@link Graph#nodes()} and

   */
  static double calculateNewMeanNonFinite(double previousMean, double value) {
    /*
     * Desired behaviour is to match the results of applying the naive mean formula. In particular,
     * the update formula can subtract infinities in cases where the naive formula would add them.
     *
     * Consequently:
     * 1. If the previous mean is finite and the new value is non-finite then the new mean is that

|               16 |              13 |                 3 |                1.23 |
|               16 |              14 |                 2 |                1.14 |

You can calculate _approximate_ storage usage ratio using the formula - total drives (N) / data drives (D).

### Allowed values for STANDARD storage class

`STANDARD` storage class implies more parity than `REDUCED_REDUNDANCY` class. So, `STANDARD` parity drives should be

     * numHashFunctions/bitSize)^n)`. Solving that for n, and approximating `ln x` as `x - 1` when x
     * is close to 1 (why?), gives the following formula.
     */
    double fractionOfBitsSet = (double) bitCount / bitSize;
    return DoubleMath.roundToLong(
        -Math.log1p(-fractionOfBitsSet) * bitSize / numHashFunctions, RoundingMode.HALF_UP);
  }

        if (!(element instanceof Long) || parent.array[i++] != (Long) element) {
          return false;
        }
      }
      return true;
    }

    // Because we happen to use the same formula. If that changes, just don't override this.
    @Override
    public int hashCode() {
      return parent.hashCode();
    }

    @Override
    public String toString() {
      return parent.toString();

        if (!(element instanceof Integer) || parent.array[i++] != (Integer) element) {
          return false;
        }
      }
      return true;
    }

    // Because we happen to use the same formula. If that changes, just don't override this.
    @Override
    public int hashCode() {
      return parent.hashCode();
    }

    @Override
    public String toString() {
      return parent.toString();

        if (!(element instanceof Integer) || parent.array[i++] != (Integer) element) {
          return false;
        }
      }
      return true;
    }

    // Because we happen to use the same formula. If that changes, just don't override this.
    @Override
    public int hashCode() {
      return parent.hashCode();
    }

    @Override
    public String toString() {
      return parent.toString();

        if (!(element instanceof Double) || !areEqual(parent.array[i++], (Double) element)) {
          return false;
        }
      }
      return true;
    }

    // Because we happen to use the same formula. If that changes, just don't override this.
    @Override
    public int hashCode() {
      return parent.hashCode();
    }

    @Override
    public String toString() {
      return parent.toString();

  <mime-type type="application/vnd.oasis.opendocument.formula">
    <alias type="application/x-vnd.oasis.opendocument.formula"/>
    <_comment>OpenDocument v1.0: Formula document</_comment>
    <magic>
      <match type="string" offset="0" value="PK">
        <match type="string" offset="30"
               value="mimetypeapplication/vnd.oasis.opendocument.formula" />
      </match>
    </magic>

    @Override
    public int hashCode() {
      // Warning: this is broken if size() == 0, so it is critical that we
      // substitute an empty ImmutableSet to the user in place of this

      // It's a weird formula, but tests prove it works.
      int adjust = size() - 1;
      for (int i = 0; i < axes.size(); i++) {
        adjust *= 31;
        adjust = ~~adjust;