Halo2-more-examples-part-2

The part 1 of this tutorial can be found here => https://github.com/enricobottazzi/halo2-fibonacci-ex/blob/master/README.md

These examples are based on this tutorial => https://learn.0xparc.org/materials/halo2/learning-group-1/exercise-1

IsZero Gadget

This is a gadget that can be used inside other circuits. We just define the Chip here as we can reuse it across different circuit components. You can find it in the is_zero.rs file.

Now we'll see how a gadget can be used inside another circuit

Example3 circuit

The circuit is executing this logic f(a, b, c) = if a == b {c} else {a - b}. We'll use the IsZero gadget to check if a == b which mean checking if a - b is zero or not.

In this example I'm using the constraint system set by the is_zero gadget + setting 2 new custom gate into our new circuit!

cargo test -- --nocapture test_example3

Example4

Simple range check circuit Config. Given a value v and a maximum range that the value, we constraint the value.

cargo test -- --nocapture test_range_check_1

cargo test --all-features -- --nocapture print_range_check_1

Example5

Extend the range check using lookup arguments. Useful when you want to check it against a large range. Create the Config to support that

cargo test -- --nocapture test_range_check_2

cargo test --all-features -- --nocapture print_range_check_2

Example6

Improvement on example5 by looking up on smaller ranges. For example, our lookup table right now is 8 bits. But sometimes we might not want to constraint for the maximum amount of 8 bits. This implementation will refine the lookup argument to support such feature.

cargo test -- --nocapture test_range_check_3

Example7

Mix this range check Config with a word decompositon Config.