Create Poseidon hash function

[critesjosh]

Problem

Poseidon is a common hash function when writing circuits--add it to the Noir stdlib.

Solution

Write the Poseidon hash function in Noir.

Additional context

We will consider giving a grant to do this.

[critesjosh]

@kevaundray can you add the noir-stdlib label to this?

[vaibhavgeek]

@TomAFrench I am working on noir implementation of poseidon hash. It would be helpful if you could share code for keccack hash in noir, it could help me if I get stuck.

My repository is public (https://github.com/vaibhavgeek/poseidon) and looking forward to collaborators.

[vaibhavgeek]

Update: Awaiting vectors / Multi dimensional arrays to be implemented in Noir before further proceeding with the same, basic implementation is completed.

Work currently on standby as communicated with @vezenovm.

[vezenovm]

Update: Awaiting vectors / Multi dimensional arrays to be implemented in Noir before further proceeding with the same, basic implementation is completed.

Work currently on standby as communicated with @vezenovm.

@vaibhavgeek From discussions with the team I cannot give an exact timeline when this will be added. This isn't currently a priority for us as multi dimensional arrays can be mocked using 1D arrays at the moment.