# Did the EvalSum() API use hoisted rotations?

**URL:** <https://openfhe.discourse.group/t/did-the-evalsum-api-use-hoisted-rotations/2207>\
**Category:** Library Questions\
**Created:** [November 7, 2025, 3:17am UTC](https://openfhe.discourse.group/t/did-the-evalsum-api-use-hoisted-rotations/2207 "2025-11-07T03:17:19Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![capibala](https://avatars.discourse-cdn.com/v4/letter/c/b5ac83/32.png) [@capibala](https://openfhe.discourse.group/u/capibala)\
**Post date:** [November 7, 2025, 3:17am UTC](https://openfhe.discourse.group/t/did-the-evalsum-api-use-hoisted-rotations/2207/1 "2025-11-07T03:17:19Z")

</div>

I saw in the previous question that EvalSumRows/Cols did not use hoisted rotations. Does EvalSum use this technique?

---

<div class="post-metadata">

**Author:** ![ypolyakov](https://yyz1.discourse-cdn.com/flex031/user_avatar/openfhe.discourse.group/ypolyakov/32/47_2.png) [@ypolyakov](https://openfhe.discourse.group/u/ypolyakov)\
**Post date:** [November 10, 2025, 4:18pm UTC](https://openfhe.discourse.group/t/did-the-evalsum-api-use-hoisted-rotations/2207/2 "2025-11-10T16:18:34Z")

</div>

No, hoisted rotations are not used for `EvalSum` either (just like in the case of [EvalSumRows/Cols](https://openfhe.discourse.group/t/do-ckks-evalsumrows-cols-implicitly-use-hoisting-for-rotations/2191)) because there are no multiple rotations for the same ciphertext. Note that that EvalSum is used as a subroutine by both EvalSumRows and EvalSumCols.