> For the complete documentation index, see [llms.txt](https://boncurs.gitbook.io/boncurs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://boncurs.gitbook.io/boncurs/boncurs-bonding-curve-library/boncurs-curve/boncurscurve.md).

# BoncursCurve

[Git Source](https://github.com/dustinstacy/boncurs/blob/7928cae257b46ede89b50d06eaae18601fcd0340/contracts/experimental/BoncursCurve.sol)

**Inherits:** BoncursFormula

This contract is used to get the purchase and sale return values for a Boncurs curve.

## Functions

### getPurchaseCost

Returns the purchase cost using a Boncurs Curve.

```solidity
function getPurchaseCost(
    uint256 supply,
    uint256 reserveBalance,
    uint256 initialCost,
    uint32 scalingFactor,
    uint256 amount
) internal pure returns (uint256 purchaseCost);
```

**Parameters**

| Name             | Type      | Description                                                                      |
| ---------------- | --------- | -------------------------------------------------------------------------------- |
| `supply`         | `uint256` | token total supply                                                               |
| `reserveBalance` | `uint256` | balance of the reserve token                                                     |
| `initialCost`    | `uint256` | initial cost of the token                                                        |
| `scalingFactor`  | `uint32`  | scaling factor, represented in basis points, 1-10000 scaling factor of the curve |
| `amount`         | `uint256` | amount of tokens to purchase                                                     |

**Returns**

| Name           | Type      | Description            |
| -------------- | --------- | ---------------------- |
| `purchaseCost` | `uint256` | cost of the conversion |

### getSaleReturn

Returns the sale value using a Boncurs Curve.

```solidity
function getSaleReturn(uint256 supply, uint256 reserveBalance, uint256 sellAmount)
    internal
    pure
    returns (uint256 saleReturn);
```

**Parameters**

| Name             | Type      | Description                  |
| ---------------- | --------- | ---------------------------- |
| `supply`         | `uint256` | token total supply           |
| `reserveBalance` | `uint256` | balance of the reserve token |
| `sellAmount`     | `uint256` | amount of tokens to sell     |

**Returns**

| Name         | Type      | Description              |
| ------------ | --------- | ------------------------ |
| `saleReturn` | `uint256` | return of the conversion |