Module halo2_gadgets::ecc::chip::constants

Constants required for the ECC chip.

Constants

• FIXED_BASE_WINDOW_SIZE
  Window size for fixed-base scalar multiplication
• H
  $2^{FIXED_BASE_WINDOW_SIZE}$
• NUM_WINDOWS
  Number of windows for a full-width scalar
• NUM_WINDOWS_SHORT
  Number of windows for a short signed scalar

Functions

• compute_lagrange_coeffs
  For each window, we interpolate the $x$-coordinate. Here, we pre-compute and store the coefficients of the interpolation polynomial.
• find_zs_and_us
  For each window, $z$ is a field element such that for each point $(x, y)$ in the window:
• test_lagrange_coeffstest-dependencies
  Test that Lagrange interpolation coefficients reproduce the correct x-coordinate for each fixed-base multiple in each window.
• test_zs_and_ustest-dependencies
  Test that the z-values and u-values satisfy the conditions: 1. z + y = u^2, 2. z - y is not a square for the y-coordinate of each fixed-base multiple in each window.