def calculate_min_iters_from_iterations(
proof_of_space: ProofOfSpace,
difficulty: uint64,
iterations: uint64,
) -> uint64:
"""
Using the total number of iterations on a block (which is encoded in the block) along with
other details, we can calculate the constant factor in iterations, which is not written into
the block.
"""
quality: bytes32 = proof_of_space.verify_and_get_quality_string()
iters_rounded = (int(difficulty) << 32) // quality_str_to_quality(
quality, proof_of_space.size)
min_iterations = uint64(iterations - iters_rounded)
assert min_iterations >= 1
return min_iterations
def calculate_iterations_quality(
quality_string: bytes32,
size: int,
difficulty: int,
cc_sp_output_hash: bytes32,
) -> uint64:
"""
Calculates the number of iterations from the quality. The quality is converted to a number
between 0 and 1, then divided by expected plot size, and finally multiplied by the
difficulty.
"""
sp_quality_string: bytes32 = std_hash(quality_string + cc_sp_output_hash)
iters = uint64(
uint128(int(difficulty) << 25) //
quality_str_to_quality(sp_quality_string, size))
return max(iters, uint64(1))
def calculate_iterations_quality(
quality: bytes32,
size: uint8,
difficulty: uint64,
min_iterations: uint64,
) -> uint64:
"""
Calculates the number of iterations from the quality. The quality is converted to a number
between 0 and 1, then divided by expected plot size, and finally multiplied by the
difficulty.
"""
iters_rounded = (int(difficulty) << 32) // quality_str_to_quality(
quality, size)
iters_final = uint64(min_iterations + iters_rounded)
assert iters_final >= 1
return iters_final