key_switch_down: Scale a ciphertext down from extended CRT basis to Q

In openfhe.R: R Interface to the 'OpenFHE' Fully Homomorphic Encryption Library

Scale a ciphertext down from extended CRT basis to Q

Description

Brings a ciphertext that lives in the extended PQ basis (for example, the output of eval_fast_rotation_ext() with hybrid key switching) back to the standard Q basis. Only supported when the scheme is configured with hybrid key switching — other key-switching techniques have no round-trip to extended PQ and therefore nothing to scale back from.

Usage

key_switch_down(ct)

Arguments

ct	A Ciphertext in the extended P*Q basis.

Value

A Ciphertext in the Q basis.

See Also

eval_fast_rotation_ext()

openfhe.R documentation built on Nov. 13, 2026, 5:07 p.m.