PowerChannelUpdateRule

Git Source

Inherits:QuantAMMGradientBasedRule, UpdateRule

Contains the logic for calculating the new weights of a QuantAMM pool using the power channel update rule

State Variables

ONE

int256 private constant ONE = 1 * 1e18;

REQUIRES_PREV_MAVG

uint16 private constant REQUIRES_PREV_MAVG = 0;

Functions

constructor

constructor(address _updateWeightRunner) UpdateRule(_updateWeightRunner);

_getWeights

w(t) = w(t − 1) + κ · ( sign(1/p(t)∂p(t)/∂t) * |1/p(t)∂p(t)/∂t|^q − ℓp(t) ) where ℓp(t) = 1/N * ∑(sign(1/p(t)∂p(t)/∂t) * |1/p(t)∂p(t)/∂t|^q)

function _getWeights(
    int256[] calldata _prevWeights,
    int256[] memory _data,
    int256[][] calldata _parameters,
    QuantAMMPoolParameters memory _poolParameters
) internal override returns (int256[] memory newWeightsConverted);

Parameters

Name	Type	Description
_prevWeights	int256[]	the previous weights retrieved from the vault
_data	int256[]	the latest data from the signal, usually price
_parameters	int256[][]	the parameters of the rule that are not lambda
_poolParameters	QuantAMMPoolParameters	pool parameters [0]=k, [1]=q, can be per token (vector) or single for all tokens (scalar), [2]=useRawPrice

_requiresPrevMovingAverage

Get the number of assets required for the rule

function _requiresPrevMovingAverage() internal pure override returns (uint16);

_setInitialIntermediateValues

Set the initial intermediate values for the rule, in this case the gradient

function _setInitialIntermediateValues(address _poolAddress, int256[] memory _initialValues, uint256 _numberOfAssets)
    internal
    override;

Parameters

Name	Type	Description
_poolAddress	address	address of pool being initialised
_initialValues	int256[]	the initial intermediate values provided
_numberOfAssets	uint256	number of assets in the pool

validParameters

Check if the given parameters are valid for the rule

If parameters are not valid, either reverts or returns false

function validParameters(int256[][] calldata parameters) external pure override returns (bool valid);

Structs

QuantAMMPowerChannelLocals

Struct to store local variables for the power channel calculation

struct to avoid stack too deep issues

struct QuantAMMPowerChannelLocals {
    int256[] kappa;
    int256[] newWeights;
    int256 normalizationFactor;
    uint256 prevWeightsLength;
    bool useRawPrice;
    uint256 i;
    int256 q;
    int256[] vectorQ;
    int256 denominator;
    int256 sumKappa;
    int256 res;
    int256 sign;
    int256 intermediateRes;
}

Properties

Name	Type	Description
kappa	int256[]	array of kappa value parameters
newWeights	int256[]	array of new weights
normalizationFactor	int256	normalization factor for the weights
prevWeightsLength	uint256	length of the previous weights
useRawPrice	bool	boolean to determine if raw price should be used or average
i	uint256	index for looping
q	int256	Q value
vectorQ	int256[]
denominator	int256	denominator for the weights
sumKappa	int256	sum of all kappa values
res	int256	result of the calculation
sign	int256	sign of the calculation
intermediateRes	int256	intermediate result of the calculation