Inverse Transform From Bit Reverse InPlace()

Library Questions
1

Hello, when in InverseTransform FromBit ReverseInPlace() function we use some maps.
For example m_rootOfUnityInverse PreconReverseTable ByModulus, I take that the “inverse” is for the inverse of the root of unity, the “reverse” is for the Bit Reversal operation and the “precon” I can’t understand what it means. This is where I need some help understanding and correct me If I got it wrong.
Also, why do we access m_cycloOrder InverseTableBy Modulus[modulus][msb] with the msb ? This msb is the index of the Most Significant Bit of the ShiftRight(Cyclotomic Order) - 1.
Thank you

2

precon is a precomputed parameter when multiplying by a constant using Shoup’s method. It corresponds to the ModMulFastConst method (see Math Backends — OpenFHE documentation for more details)

Lookup by msb implies that different ring dimensions (half the cyclotomic order) are supported by the map.

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