> For the complete documentation index, see [llms.txt](https://docs.kyberswap.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.kyberswap.com/reference/legacy/api-abi/core-smart-contracts/ikybermatchingengine.md).

# IKyberMatchingEngine

{% hint style="warning" %}
You are referring to the **`Legacy`** version of KyberSwap docs.

For the most updated information, please refer to:

* [**`Classic`**](https://github.com/KyberNetwork/kyberswap-documentation/blob/main/reference/legacy/api-abi/core-smart-contracts/broken-reference/README.md)
* [**`Elastic`**](/reference/legacy/kyberswap-elastic.md)
* [**`Limit Order`**](/kyberswap-solutions/limit-order.md)
* [**`Aggregator`**](/kyberswap-solutions/kyberswap-aggregator.md)
  {% endhint %}

## interface IKyberMatchingEngine

is [IKyberReserve](https://docs.kyberswap.com/Legacy/api-abi/core-smart-contracts/api_abi-ikyberreserve.md), [IKyberNetwork](https://docs.kyberswap.com/Legacy/api-abi/core-smart-contracts/api_abi-ikybernetwork.md), [IKyberStorage](https://docs.kyberswap.com/Legacy/api-abi/core-smart-contracts/api_abi-ikyberstorage.md)\\

*Source*: [IKyberMatchingEngine.sol](https://github.com/KyberNetwork/smart-contracts/blob/master/contracts/sol6/IKyberMatchingEngine.sol)

***

### INDEX[​](https://docs.kyberswap.com/Legacy/api-abi/core-smart-contracts/api_abi-ikybermatchingengine#index) <a href="#index" id="index"></a>

\<AUTOGENERATED\_TABLE\_OF\_CONTENTS>

### REFERENCE[​](https://docs.kyberswap.com/Legacy/api-abi/core-smart-contracts/api_abi-ikybermatchingengine#reference) <a href="#reference" id="reference"></a>

#### Functions[​](https://docs.kyberswap.com/Legacy/api-abi/core-smart-contracts/api_abi-ikybermatchingengine#functions) <a href="#functions" id="functions"></a>

#### `getNegligibleRateDiffBps`[​](https://docs.kyberswap.com/Legacy/api-abi/core-smart-contracts/api_abi-ikybermatchingengine#getnegligibleratediffbps) <a href="#getnegligibleratediffbps" id="getnegligibleratediffbps"></a>

Returns the negligible rate difference in BPS.

***

function **getNegligibleRateDiffBps**() external view returns (uint256)\ **Returns:**\ The negligible rate difference in BPS.

\
\### \`getTradingReserves\` Returns trading reserves info for a trade. \_\_\_ function \_\_getTradingReserves\_\_(IERC20 src, IERC20 dest, bool isTokenToToken, bytes hint) external returns (bytes32\[] reserveIds, uint256\[] splitValuesBps, ProcessWithRate processWithRate) | Parameter | Type | Description | | --------- |:-----:|:-----------:| | \`src\` | IERC20 | source token address | | \`dest\` | IERC20 | destination token address | | \`isTokenToToken\` | bool | whether the trade is token -> token | | \`hint\` | bytes | encoded hint for reserve routing | \*\*Returns:\*\*\ reserveIds - array of 32-byte reserve IDs for the trade splitValuesBps - array of split values in BPS for the trade respective to reserveIds processWithRate - whether extra processing is required or not\
\### \`doMatch\` Returns the indexes of the best rate from the rates array for token -> eth or eth -> token trade. \_\_\_ function \_\_doMatch\_\_(IERC20 src, IERC20 dest, uint256\[] srcAmounts, uint256\[] feesAccountedDestBps, uint256\[] rates) external view returns (uint256\[] reserveIndexes) | Parameter | Type | Description | | --------- |:-----:|:-----------:| | \`src\` | IERC20 | source token address | | \`dest\` | IERC20 | destination token address | | \`srcAmounts\` | uint256\[] | array of srcAmounts after deducting fees: | | \`feesAccountedDestBps\` | uint256\[] | fees charged in BPS, to be deducted from calculated destAmount | | \`rates\` | uint256\[] | array of rates queried from reserves | \*\*Returns:\*\*\ reserveIndexes - array of the indexes most suited for the trade


---

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