Merge pull request #2712 from XRPLF/amm-modular-tutorials

AMM modular tutorials.

docs/tutorials/javascript/amm/add-assets-to-amm.md

@@ -0,0 +1,875 @@
+# Add Assets to an AMM
+
+Follow the steps from the [Create an AMM](/docs/tutorials/javascript/amm/create-an-amm/) tutorial before proceeding.
+
+This example shows how to:
+
+1. Deposit assets to an existing AMM and receive LP tokens.
+2. Vote on AMM trading fees.
+3. Check the value of your LP tokens.
+4. Redeem LP tokens for assets in the AMM pair.
+
+[![Add assets to AMM test harness](/docs/img/quickstart-add-to-amm1.png)](/docs/img/quickstart-add-to-amm1.png)
+
+You can download the [Quickstart Samples](https://github.com/XRPLF/xrpl-dev-portal/tree/master/_code-samples/quickstart/js/)<!-- {.github-code-download} --> archive to try each of the samples in your own browser.
+
+{% admonition type="note" name="Note" %}
+Without the Quickstart Samples, you will not be able to try the examples that follow.
+{% /admonition %}
+
+
+## Usage
+
+### Get Accounts
+
+1. Open `12.add-to-amm.html` in a browser.
+2. Select **Testnet** or **Devnet**
+3. Get test accounts.
+   - If you have existing account seeds:
+     1. Paste account seeds in the **Seeds** field.
+     2. Click **Get Accounts from Seeds**.
+   - If you don't have account seeds:
+     1. Click **Get New Standby Account**.
+     2. Click **Get New Operational Account**.
+
+[![Get account results](/docs/img/quickstart-add-to-amm2.png)](/docs/img/quickstart-add-to-amm2.png)
+
+
+### Get the AMM
+
+Use the information from either the XRP/Token or Token/Token AMM you created in [Create an AMM](/docs/tutorials/javascript/amm/create-an-amm/#create-an-xrp/token-amm).
+
+1. Enter a [currency code](/docs/references/protocol/data-types/currency-formats.md#currency-codes) in the **Asset 1 Currency** field. For example, `XRP`.
+2. Enter a second currency code in the **Asset 2 Currency** field. For example, `TST`.
+3. Enter the operational account address in the **Asset 2 Issuer** field.
+4. Click **Check AMM**.
+
+[![Get AMM results](/docs/img/quickstart-add-to-amm3.png)](/docs/img/quickstart-add-to-amm3.png)
+
+
+### Deposit a Single Asset to the AMM
+
+You can deposit either asset, but depositing only one asset reduces the amount of LP tokens you receive.
+
+1. Click **Get Balances** to verify how many tokens you have.
+2. Enter a value in the **Asset 1 Amount** field.
+3. Click **Add to AMM**.
+
+[![Add assets to AMM results](/docs/img/quickstart-add-to-amm4.png)](/docs/img/quickstart-add-to-amm4.png)
+
+
+### Deposit Both Assets to the AMM
+
+1. Click **Get Balances** to verify how many tokens you have.
+2. Enter a value in the **Asset 1 Amount** field.
+3. Enter a value in the **Asset 2 Amount** field.
+4. Click **Add to AMM**.
+
+[![Add assets to AMM results](/docs/img/quickstart-add-to-amm5.png)](/docs/img/quickstart-add-to-amm5.png)
+
+
+### Vote on trading fees
+
+1. Enter a value in the **Trading Fee** field. The proposed fee is in units of 1/100,000; a value of 1 is equivalent to 0.001%. The maximum value is 1000, indicating a 1% fee.
+2. Click **Vote on Fee**.
+
+[![Vote on trading fees results](/docs/img/quickstart-add-to-amm6.png)](/docs/img/quickstart-add-to-amm6.png)
+
+
+### Redeem Your LP Tokens
+
+1. Click **Get LP Value**.
+2. Enter a value in the **LP Tokens** field.
+3. Click **Redeem LP**.
+
+[![Get LP token value results](/docs/img/quickstart-add-to-amm7.png)](/docs/img/quickstart-add-to-amm7.png)
+
+
+## Code Walkthrough
+
+You can open `ripplex12-add-to-amm.js` from the [Quickstart Samples](https://github.com/XRPLF/xrpl-dev-portal/tree/master/_code-samples/quickstart/js/) to view the source code.
+
+
+### Add Assets to an Existing AMM
+
+This code checks if you're trying to add one or both assets, and then modifies the `AMMDeposit` transaction to be either a single or double-asset deposit.
+
+```javascript
+async function addAssets() {
+```
+
+Connect to the XRP Ledger.
+
+```javascript
+  let net = getNet()
+
+  const client = new xrpl.Client(net)
+  results = `\n\nConnecting to ${getNet()} ...`
+  standbyResultField.value = results
+
+  await client.connect()
+  results += '\n\nConnected.'
+  standbyResultField.value = results
+```
+
+Get the AMM information fields.
+
+```javascript
+  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
+
+  const asset1_currency = asset1CurrencyField.value
+  const asset1_issuer = asset1IssuerField.value
+  const asset1_amount = asset1AmountField.value
+
+  const asset2_currency = asset2CurrencyField.value
+  const asset2_issuer = asset2IssuerField.value
+  const asset2_amount = asset2AmountField.value
+```
+
+Format the `AMMDeposit` transaction based on the combination of `XRP` and tokens.
+
+```javascript
+  // Check for all combinations of asset deposits.
+  let ammdeposit = null
+
+  if (asset1_currency == "XRP" && asset2_currency && asset1_amount && asset2_amount ) {
+    
+    ammdeposit = {
+      "TransactionType": "AMMDeposit",
+      "Asset": {
+        currency: "XRP"
+      },
+      "Asset2": {
+        currency: asset2_currency,
+        issuer: asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "Amount": xrpl.xrpToDrops(asset1_amount),
+      "Amount2": {
+        currency: asset2_currency,
+        issuer: asset2_issuer,
+        value: asset2_amount
+      },
+      "Flags": 0x00100000
+    }
+
+  } else if ( asset1_currency && asset2_currency == "XRP" && asset1_amount && asset2_amount ) {
+
+    ammdeposit = {
+      "TransactionType": "AMMDeposit",
+      "Asset": {
+        currency: asset1_currency,
+        issuer: asset1_issuer
+      },
+      "Asset2": {
+        currency: "XRP"
+      },
+      "Account": standby_wallet.address,
+      "Amount": {
+        currency: asset1_currency,
+        issuer: asset1_issuer,
+        value: asset1_amount
+      },
+      "Amount2": xrpl.xrpToDrops(asset2_amount),
+      "Flags": 0x00100000
+    }
+
+  } else if ( asset1_currency && asset2_currency && asset1_amount && asset2_amount ) {
+
+    ammdeposit = {
+      "TransactionType": "AMMDeposit",
+      "Asset": {
+        currency: asset1_currency,
+        issuer: asset1_issuer
+      },
+      "Asset2": {
+        currency: asset2_currency,
+        issuer: asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "Amount": {
+        currency: asset1_currency,
+        issuer: asset1_issuer,
+        value: asset1_amount
+      },
+      "Amount2": {
+        currency: asset2_currency,
+        issuer: asset2_issuer,
+        value: asset2_amount
+      },
+      "Flags": 0x00100000
+    }
+
+  } else if ( asset1_currency == "XRP" && asset2_currency && asset1_amount ) {
+
+    ammdeposit = {
+      "TransactionType": "AMMDeposit",
+      "Asset": {
+        currency: "XRP"
+      },
+      "Asset2": {
+        currency: asset2_currency,
+        issuer: asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "Amount": xrpl.xrpToDrops(asset1_amount),
+      "Flags": 0x00080000
+    }
+
+  } else if ( asset1_currency && asset2_currency == "XRP" && asset1_amount ) {
+
+    ammdeposit = {
+      "TransactionType": "AMMDeposit",
+      "Asset": {
+        currency: asset1_currency,
+        issuer: asset1_issuer
+      },
+      "Asset2": {
+        currency: "XRP"
+      },
+      "Account": standby_wallet.address,
+      "Amount": {
+        currency: asset1_currency,
+        issuer: asset1_issuer,
+        value: asset1_amount
+      },
+      "Flags": 0x00080000
+    }
+
+  } else if ( asset1_currency == "XRP" && asset2_currency && asset2_amount ) {
+
+    ammdeposit = {
+      "TransactionType": "AMMDeposit",
+      "Asset": {
+        currency: "XRP"
+      },
+      "Asset2": {
+        currency: asset2_currency,
+        issuer: asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "Amount": {
+        currency: asset2_currency,
+        issuer: asset2_issuer,
+        value: asset2_amount
+      },
+      "Flags": 0x00080000
+    }
+
+  } else if ( asset1_currency && asset2_currency && asset1_amount ) {
+
+    ammdeposit = {
+      "TransactionType": "AMMDeposit",
+      "Asset": {
+        currency: asset1_currency,
+        issuer: asset1_issuer
+      },
+      "Asset2": {
+        currency: asset2_currency,
+        issuer: asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "Amount": {
+        currency: asset1_currency,
+        issuer: asset1_issuer,
+        value: asset1_amount
+      },
+      "Flags": 0x00080000
+    }
+
+  } else if ( asset1_currency && asset2_currency && asset2_amount ) {
+
+    ammdeposit = {
+      "TransactionType": "AMMDeposit",
+      "Asset": {
+        currency: asset1_currency,
+        issuer: asset1_issuer
+      },
+      "Asset2": {
+        currency: asset2_currency,
+        issuer: asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "Amount": {
+        currency: asset2_currency,
+        issuer: asset2_issuer,
+        value: asset2_amount
+      },
+      "Flags": 0x00080000
+    }
+
+  } else {
+
+    results += `\n\nNo assets selected to add ...`
+    standbyResultField.value = results
+    standbyResultField.scrollTop = standbyResultField.scrollHeight
+    return
+
+  }
+```
+
+Prepare the transaction for submission. Wrap the submission in a `try-catch` block to handle any errors.
+
+```javascript
+  try {
+ 
+  const prepared_deposit = await client.autofill(ammdeposit)
+  results += `\n\nPrepared transaction:\n${JSON.stringify(prepared_deposit, null, 2)}`
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight
+```
+
+Sign the transaction using the standby account wallet.
+
+```javascript
+  const signed_deposit = standby_wallet.sign(prepared_deposit)
+  results += `\n\nSending AMMDeposit transaction ...`
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight
+```
+
+Submit the signed transaction to the XRPL. Run the `checkAMM()` function to update the AMM's information in the AMM log on a successful transaction.
+
+```javascript
+  const lp_deposit = await client.submitAndWait(signed_deposit.tx_blob)
+  
+  if (lp_deposit.result.meta.TransactionResult == "tesSUCCESS") {
+    results += `\n\nTransaction succeeded.`
+    checkAMM()
+  } else {
+    results += `\n\nError sending transaction: ${JSON.stringify(lp_deposit.result.meta.TransactionResult, null, 2)}`
+  }
+
+  } catch (error) {
+    results += `\n\n${error.message}`
+  }
+```
+
+Report the transaction results in the standby account log.
+
+```javascript
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight
+
+  client.disconnect()
+
+}
+```
+
+
+### Vote on Trading Fees
+
+Trading fees are applied to any transaction that interacts with the AMM. As with the `addAssets()` function, this one checks the combination of assets provided to modifty the `ammVote` transaction.
+
+```javascript
+async function voteFees() {
+```
+
+Connect to the XRP Ledger.
+
+```javascript
+  let net = getNet()
+
+  const client = new xrpl.Client(net)
+  results = `\n\nConnecting to ${getNet()} ...`
+  standbyResultField.value = results
+
+  await client.connect()
+  results += '\n\nConnected.'
+  standbyResultField.value = results
+```
+
+Get the AMM information and vote fee fields.
+
+```javascript
+  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
+  const voteFee = standbyFeeField.value
+
+  const asset1_currency = asset1CurrencyField.value
+  const asset1_issuer = asset1IssuerField.value
+
+  const asset2_currency = asset2CurrencyField.value
+  const asset2_issuer = asset2IssuerField.value
+```
+
+Format the `AMMVote` transaction based on the combination of `XRP` and tokens.
+
+```javascript
+  let ammvote = null
+
+  if ( asset1_currency == "XRP" ) {
+
+    ammvote = {
+      "TransactionType": "AMMVote",
+      "Asset": {
+        "currency": "XRP"
+      },
+      "Asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "TradingFee": Number(voteFee)
+    }
+
+  } else if ( asset2_currency == "XRP" ) {
+
+    ammvote = {
+      "TransactionType": "AMMVote",
+      "Asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "Asset2": {
+        "currency": "XRP"
+      },
+      "Account": standby_wallet.address,
+      "TradingFee": Number(voteFee)
+    }
+  } else {
+
+    ammvote = {
+      "TransactionType": "AMMVote",
+      "Asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "Asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "TradingFee": Number(voteFee)
+    }
+
+  }
+```
+
+Prepare the transaction for submission. Wrap the submission in a `try-catch` block to handle any errors.
+
+```javascript
+  try {
+  
+  const prepared_vote = await client.autofill(ammvote)
+  results += `\n\nPrepared transaction:\n${JSON.stringify(prepared_vote, null, 2)}`
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight
+```
+
+Sign the prepared transaction using the standby account wallet.
+
+```javascript
+  const signed_vote = standby_wallet.sign(prepared_vote)
+  results += `\n\nSending AMMVote transaction ...`
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight  
+```
+
+Submit the signed transaction to the XRPL. Run the `checkAMM()` function to update the AMM's information in the AMM log on a successful transaction.
+
+```javascript
+  const response_vote = await client.submitAndWait(signed_vote.tx_blob)
+  if (response_vote.result.meta.TransactionResult == "tesSUCCESS") {
+    results += `\n\nTransaction succeeded.`
+    checkAMM()
+  } else {
+    results += `\n\nError sending transaction: ${JSON.stringify(response_vote.result.meta.TransactionResult, null, 2)}`
+  }
+
+} catch (error) {
+  results += `\n\n${error.message}`
+}
+```
+
+Report the transaction results in the standby account log.
+
+```javascript
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight  
+
+  client.disconnect()
+
+}
+```
+
+
+### Calculate the Value of Your LP Tokens
+
+This function gets your LP token balance and calculates what you can withdraw from the AMM.
+
+```javascript
+async function calculateLP() {
+```
+
+Connect to the XRP Ledger.
+
+```javascript
+  let net = getNet()
+
+  const client = new xrpl.Client(net)
+  results = `\n\nConnecting to ${getNet()} ...`
+  standbyResultField.value = results
+
+  await client.connect()
+  results += '\n\nConnected.'
+  standbyResultField.value = results
+```
+
+Get the AMM information fields.
+
+```javascript
+  const standby_wallet = standbyAccountField.value
+
+  const asset1_currency = asset1CurrencyField.value
+  const asset1_issuer = asset1IssuerField.value
+
+  const asset2_currency = asset2CurrencyField.value
+  const asset2_issuer = asset2IssuerField.value
+```
+
+Format the `amm_info` command based on the combination of `XRP` and tokens.
+
+```javascript
+  let amm_info = null
+
+  if ( asset1_currency == "XRP" ) {
+  
+    amm_info = {
+      "command": "amm_info", 
+      "asset": {
+        "currency": "XRP"
+      },
+      "asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      }
+    }
+  
+  } else if ( asset2_currency == "XRP" ) {
+
+    amm_info = {
+      "command": "amm_info", 
+      "asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "asset2": {
+        "currency": "XRP"
+      }
+    }
+
+  } else {
+
+    amm_info = {
+      "command": "amm_info", 
+      "asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      }
+    }
+
+  }
+```
+
+Get the standby account wallet balances and AMM details. Wrap the code in a `try-catch` block to handle any errors.
+
+```javascript
+  try {
+  
+  // Get LP token balance.
+  standbyWalletBalances = await client.getBalances(standby_wallet)
+
+  const amm_info_result = await client.request(amm_info)
+```
+
+Get the AMM account address. Any LP tokens received from depositing to the AMM is considered an issued token by that AMM account. Use the AMM account to find the LP token in the wallet balances and get the LP token balance.
+
+```javascript
+  // Get the AMM account address that issues LP tokens to depositors
+  ammAccount = amm_info_result.result.amm.account
+
+  const lpCurrency = standbyWalletBalances.find(item => item.issuer === ammAccount);
+
+  const lpBalance = lpCurrency ? lpCurrency.value : 'Currency not found';
+```
+
+Check the AMM `value` fields to format the response. `XRP` is only reported as drops and doesn't have a `value` field. Although there isn't a dedicated method to calculate what you can redeem your LP tokens for, the math to do so is simple. The code checks the percentage of LP tokens in circulation that you own, and then applies that same percentage to the total assets in the AMM to give you their redemption value.
+
+```javascript
+  const my_share = lpBalance / amm_info_result.result.amm.lp_token.value
+
+  let my_asset1 = null
+  let my_asset2 = null
+
+  if ( amm_info_result.result.amm.amount.value && amm_info_result.result.amm.amount2.value ) {
+
+    my_asset1 = amm_info_result.result.amm.amount.value * my_share
+    my_asset2 = amm_info_result.result.amm.amount2.value * my_share
+
+    results += `\n\nI have a total of ${lpBalance} LP tokens that are worth:\n
+    ${amm_info_result.result.amm.amount.currency}: ${my_asset1}
+    ${amm_info_result.result.amm.amount2.currency}: ${my_asset2}`
+
+  } else if ( amm_info_result.result.amm.amount.value == undefined ) {
+
+    my_asset1 = (amm_info_result.result.amm.amount * my_share) / 1000000
+    my_asset2 = amm_info_result.result.amm.amount2.value * my_share
+
+    results += `\n\nI have a total of ${lpBalance} LP tokens that are worth:\n
+    XRP: ${my_asset1}
+    ${amm_info_result.result.amm.amount2.currency}: ${my_asset2}`
+
+  } else {
+
+    my_asset1 = amm_info_result.result.amm.amount.value * my_share
+    my_asset2 = (amm_info_result.result.amm.amount2 * my_share) / 1000000
+
+    results += `\n\nI have a total of ${lpBalance} LP tokens that are worth:\n
+    ${amm_info_result.result.amm.amount.currency}: ${my_asset1}
+    XRP: ${my_asset2}`
+
+  }
+
+  } catch (error) {
+    results += `\n\n${error.message}`
+  }
+```
+
+Report the transaction results in the standby account log.
+
+```javascript
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight
+
+  client.disconnect()
+
+}
+```
+
+
+### Redeem Your LP Tokens
+
+The code to redeem the LP tokens checks how many tokens you want to redeem, as well as the combination of assets to format `amm_info` and `AMMWithdraw`.
+
+```javascript
+async function redeemLP() {
+```
+
+Connect to the XRP Ledger.
+
+```javascript
+  let net = getNet()
+
+  const client = new xrpl.Client(net)
+  results = `\n\nConnecting to ${getNet()} ...`
+  standbyResultField.value = results
+
+  await client.connect()
+  results += '\n\nConnected.'
+  standbyResultField.value = results
+```
+
+Get the AMM information fields.
+
+```javascript
+  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
+
+  const asset1_currency = asset1CurrencyField.value
+  const asset1_issuer = asset1IssuerField.value
+
+  const asset2_currency = asset2CurrencyField.value
+  const asset2_issuer = asset2IssuerField.value
+```
+
+Format the `amm_info` command based on the combination of `XRP` and tokens.
+
+```javascript
+  // Structure "amm_info" command based on asset combo.
+  let amm_info = null
+
+  if ( asset1_currency == "XRP" ) {
+  
+    amm_info = {
+      "command": "amm_info", 
+      "asset": {
+        "currency": "XRP"
+      },
+      "asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      }
+    }
+  
+  } else if ( asset2_currency == "XRP" ) {
+
+    amm_info = {
+      "command": "amm_info", 
+      "asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "asset2": {
+        "currency": "XRP"
+      }
+    }
+
+  } else {
+
+    amm_info = {
+      "command": "amm_info", 
+      "asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      }
+    }
+
+  }
+```
+
+Get the LP token information from the AMM.
+
+```javascript
+  // Get LP token info.
+
+  let ammIssuer = null
+  let ammCurrency = null
+  const LPTokens = standbyLPField.value
+
+  try {
+  const amm_info_result = await client.request(amm_info)
+  ammIssuer = amm_info_result.result.amm.lp_token.issuer
+  ammCurrency = amm_info_result.result.amm.lp_token.currency
+  } catch (error) {
+    results += `\n\n${error.message}`
+    standbyResultField.value = results
+    standbyResultField.scrollTop = standbyResultField.scrollHeight
+    return
+  }
+```
+
+Format the `AMMWithdraw` transaction based on the combination of `XRP` and tokens. Add the LP token info into the transaction from the `amm_info` query.
+
+```javascript
+  // Structure ammwithdraw transaction based on asset combo.
+  let ammwithdraw = null
+
+  if ( asset1_currency == "XRP" ) {
+
+    ammwithdraw = {
+      "TransactionType": "AMMWithdraw",
+      "Asset": {
+        "currency": "XRP"
+      },
+      "Asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "LPTokenIn": {
+        currency: ammCurrency,
+        issuer: ammIssuer,
+        value: LPTokens
+      },
+      "Flags": 0x00010000
+    }
+
+  } else if ( asset2_currency == "XRP" ) {
+
+    ammwithdraw = {
+      "TransactionType": "AMMWithdraw",
+      "Asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "Asset2": {
+        "currency": "XRP"
+      },
+      "Account": standby_wallet.address,
+      "LPTokenIn": {
+        currency: ammCurrency,
+        issuer: ammIssuer,
+        value: LPTokens
+      },
+      "Flags": 0x00010000
+    }
+
+  } else {
+
+    ammwithdraw = {
+      "TransactionType": "AMMWithdraw",
+      "Asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "Asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      },
+      "Account": standby_wallet.address,
+      "LPTokenIn": {
+        currency: ammCurrency,
+        issuer: ammIssuer,
+        value: LPTokens
+      },
+      "Flags": 0x00010000
+    }
+
+  }
+```
+
+Prepare the transaction for submission. Wrap the submission in a `try-catch` block to handle any errors.
+
+```javascript
+  try {
+
+  const prepared_withdraw = await client.autofill(ammwithdraw)
+  results += `\n\nPrepared transaction:\n${JSON.stringify(prepared_withdraw, null, 2)}`
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight    
+```
+
+Sign the prepared transaction with the standby account wallet.
+
+```javascript
+  const signed_withdraw = standby_wallet.sign(prepared_withdraw)
+  results += `\n\nSending AMMWithdraw transaction ...`
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight
+```
+
+Submit the signed transaction to the XRPL. Update the AMM info log and get wallet balances on a successful transaction.
+
+```javascript
+  const response_withdraw = await client.submitAndWait(signed_withdraw.tx_blob)
+  
+  if (response_withdraw.result.meta.TransactionResult == "tesSUCCESS") {
+    results += `\n\nTransaction succeeded.`
+    checkAMM()
+    getBalances()
+  } else {
+    results += `\n\nError sending transaction: ${JSON.stringify(response_withdraw.result.meta.TransactionResult, null, 2)}`
+  }
+
+  } catch (error) {
+    results += `\n\n${error.message}`
+  }
+```
+
+Report the transaction results to the standby account log.
+
+```javascript
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight
+
+  client.disconnect()
+
+}
+```

docs/tutorials/javascript/amm/create-an-amm.md

@@ -0,0 +1,359 @@
+# Create an AMM
+
+This example shows how to:
+
+1. Check if an AMM pair exists.
+2. Issue a token.
+3. Create an AMM pair with the issued tokens and XRP.
+4. Create another AMM pair with two issued tokens.
+
+[![Create AMM test harness](/docs/img/quickstart-create-amm1.png)](/docs/img/quickstart-create-amm1.png)
+
+You can download the [Quickstart Samples](https://github.com/XRPLF/xrpl-dev-portal/tree/master/_code-samples/quickstart/js/)<!-- {.github-code-download} --> archive to try each of the samples in your own browser.
+
+{% admonition type="note" name="Note" %}
+Without the Quickstart Samples, you will not be able to try the examples that follow.
+{% /admonition %}
+
+
+## Usage
+
+### Get Accounts
+
+1. Open `11.create-amm.html` in a browser.
+2. Select **Testnet** or **Devnet**
+3. Get test accounts.
+   - If you have existing account seeds:
+     1. Paste account seeds in the **Seeds** field.
+     2. Click **Get Accounts from Seeds**.
+   - If you don't have account seeds:
+     1. Click **Get New Standby Account**.
+     2. Click **Get New Operational Account**.
+
+[![Get account results](/docs/img/quickstart-create-amm2.png)](/docs/img/quickstart-create-amm2.png)
+
+
+### Check AMM
+
+Check if an AMM pair already exists. An AMM holds two different assets: at most one of these can be XRP, and one or both of them can be [tokens](/docs/concepts/tokens).
+
+1. Enter a [currency code](/docs/references/protocol/data-types/currency-formats.md#currency-codes) in the **Asset 1 Currency** field. For example, `XRP`.
+2. Enter a second currency code in the **Asset 2 Currency** field. For example, `TST`.
+3. Enter the operational account address in the **Asset 2 Issuer** field.
+4. Click **Check AMM**.
+
+[![Check AMM results](/docs/img/quickstart-create-amm3.png)](/docs/img/quickstart-create-amm3.png)
+
+
+### Create Trustline
+
+Create a trustline from the operational account to the standby account. In the standby account fields:
+
+1. Enter a maximum transfer limit in the **Amount** field, such as 10,000.
+2. Enter the operational account address in the **Destination** field.
+3. Enter a currency code in the **Currency** field. For example, `TST`.
+4. Click **Create Trustline**.
+
+[![Create trustline results](/docs/img/quickstart-create-amm4.png)](/docs/img/quickstart-create-amm4.png)
+
+
+### Issue Tokens
+
+Send issued tokens from the operational account to the standby account. In the operational account fields:
+
+1. Select **Allow Rippling** and click **Configure Account**.
+2. Enter a value in the **Amount** field, up to the maximum transfer amount you set in the trustline.
+3. Enter the standby account address in the **Destination** field.
+4. Enter the currency code from the trustline in the **Currency** field.
+5. Click **Send Currency**.
+
+[![Issue token results](/docs/img/quickstart-create-amm5.png)](/docs/img/quickstart-create-amm5.png)
+
+
+### Create an XRP/Token AMM
+
+Create a new AMM pool with XRP and the issued tokens.
+
+1. Enter `XRP` in the **Asset 1 Currency** field.
+2. Enter an amount of XRP in the **Asset 1 Amount** field. Save some `XRP` for later use in the tutorial.
+3. Enter the currency code of your issued tokens in the **Asset 2 Currency** field.
+4. Enter the operational account address in the **Asset 2 Issuer** field.
+5. Enter an amount in the **Asset 2 Amount** field.
+6. Click **Create AMM**.
+
+{% admonition type="note" name="Note" %}
+Save the seed values of the standby and operational accounts for subsequent AMM tutorials.
+{% /admonition %}
+
+[![Create AMM results](/docs/img/quickstart-create-amm6.png)](/docs/img/quickstart-create-amm6.png)
+
+
+### Create a Token/Token AMM
+
+Create a second AMM pool with two issued tokens.
+
+1. Repeat the steps from [Create Trustline](#create-trustline), using a different currency code. For example, `FOO`.
+2. Repeat the steps from [Issue Tokens](#issue-tokens), using the second currency.
+3. Enter the first currency code in the **Asset 1 Currency** field.
+4. Enter the operational account address in the **Asset 1 Issuer** field.
+5. Enter an amount in the **Asset 1 Amount** field.
+6. Enter the second currency code in the **Asset 2 Currency** field.
+7. Enter the operaional account address in the **Asset 2 Issuer** field.
+8. Enter an amount in the **Asset 2 Amount** field.
+9. Click **Create AMM**.
+
+[![Create AMM results](/docs/img/quickstart-create-amm7.png)](/docs/img/quickstart-create-amm7.png)
+
+
+## Code Walkthrough
+
+You can open `ripplex11-create-amm.js` from the [Quickstart Samples](https://github.com/XRPLF/xrpl-dev-portal/tree/master/_code-samples/quickstart/js/) to view the source code.
+
+
+### Create AMM
+
+This sends the `AMMCreate` transaction and creates a new AMM, using the initial assets provided. The code checks the token currency fields and formats the `AMMCreate` transaction based on the combination of `XRP` and custom tokens.
+
+```javascript
+async function createAMM() {
+```
+
+Connect to the XRP Ledger.
+
+```javascript
+  let net = getNet()
+
+  const client = new xrpl.Client(net)
+  results = `\n\nConnecting to ${getNet()} ...`
+  standbyResultField.value = results
+
+  await client.connect()
+  results += '\n\nConnected.'
+  standbyResultField.value = results
+```
+
+Get the AMM information fields.
+
+```javascript
+  const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
+
+  const asset1_currency = asset1CurrencyField.value
+  const asset1_issuer = asset1IssuerField.value
+  const asset1_amount = asset1AmountField.value
+
+  const asset2_currency = asset2CurrencyField.value
+  const asset2_issuer = asset2IssuerField.value
+  const asset2_amount = asset2AmountField.value
+```
+
+Format the `AMMCreate` transaction based on the combination of `XRP` and tokens.
+
+```javascript
+  let ammCreate = null
+  
+  results += '\n\nCreating AMM ...'
+  standbyResultField.value = results
+  
+  // AMMCreate requires burning one owner reserve. We can look up that amount
+  // (in drops) on the current network using server_state:
+  const ss = await client.request({"command": "server_state"})
+  const amm_fee_drops = ss.result.state.validated_ledger.reserve_inc.toString()
+
+  if (asset1_currency == 'XRP') {
+
+    ammCreate = {
+      "TransactionType": "AMMCreate",
+      "Account": standby_wallet.address,
+      "Amount": JSON.stringify(asset1_amount * 1000000), // convert XRP to drops
+      "Amount2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer,
+        "value": asset2_amount
+      },
+      "TradingFee": 500, // 500 = 0.5%
+      "Fee": amm_fee_drops
+    }
+
+  } else if (asset2_currency =='XRP') {
+
+    ammCreate = {
+      "TransactionType": "AMMCreate",
+      "Account": standby_wallet.address,
+      "Amount": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer,
+        "value": asset1_amount
+      },
+      "Amount2": JSON.stringify(asset2_amount * 1000000), // convert XRP to drops
+      "TradingFee": 500, // 500 = 0.5%
+      "Fee": amm_fee_drops
+    }
+
+  } else {
+
+    ammCreate = {
+      "TransactionType": "AMMCreate",
+      "Account": standby_wallet.address,
+      "Amount": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer,
+        "value": asset1_amount
+      },
+      "Amount2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer,
+        "value": asset2_amount
+      },
+      "TradingFee": 500, // 500 = 0.5%
+      "Fee": amm_fee_drops
+    }
+    
+  }
+```
+
+Prepare the transaction for submission. Wrap the submission in a `try-catch` block to handle any errors.
+
+```javascript
+  try {
+ 
+    const prepared_create = await client.autofill(ammCreate)
+    results += `\n\nPrepared transaction:\n${JSON.stringify(prepared_create, null, 2)}`
+    standbyResultField.value = results
+    standbyResultField.scrollTop = standbyResultField.scrollHeight  
+```
+
+Sign the prepared transaction using the standy account wallet.
+
+```javascript
+    const signed_create = standby_wallet.sign(prepared_create)
+    results += `\n\nSending AMMCreate transaction ...`
+    standbyResultField.value = results
+    standbyResultField.scrollTop = standbyResultField.scrollHeight
+```
+
+Submit the signed transaction to the XRPL.
+
+```javascript
+    const amm_create = await client.submitAndWait(signed_create.tx_blob)
+    
+    if (amm_create.result.meta.TransactionResult == "tesSUCCESS") {
+      results += `\n\nTransaction succeeded.`
+    } else {
+      results += `\n\nError sending transaction: ${JSON.stringify(amm_create.result.meta.TransactionResult, null, 2)}`
+    }
+  
+  } catch (error) {
+    results += `\n\n${error.message}`
+  }
+```
+
+Report the transaction results in the standby account log. Run the `checkAMM()` function to update the AMM's information in the AMM log.
+
+```javascript
+  standbyResultField.value = results
+  standbyResultField.scrollTop = standbyResultField.scrollHeight
+
+  checkAMM()
+      
+  client.disconnect()
+  
+}
+```
+
+
+### Check AMM
+
+This checks if an AMM already exists. While multiple tokens can share the same currency code, each issuer makes them unique. If the AMM pair exists, this responds with the AMM information, such as token pair, trading fees, etc.
+
+```javascript
+async function checkAMM() {
+```
+
+Connect to the XRP Ledger.
+
+```javascript
+  let net = getNet()
+  const client = new xrpl.Client(net)
+  await client.connect()
+```
+
+Get the AMM info fields. When checking an AMM, you only need the currency code and issuer.
+
+```javascript
+  // Gets the issuer and currency code
+  const asset1_currency = asset1CurrencyField.value
+  const asset1_issuer = asset1IssuerField.value
+
+  const asset2_currency = asset2CurrencyField.value
+  const asset2_issuer = asset2IssuerField.value
+```
+
+Format the `amm_info` command based on the combination of `XRP` and tokens.
+
+```javascript
+  let amm_info_request = null
+
+  // Get AMM info transaction
+
+  if (asset1_currency == 'XRP') {
+
+    amm_info_request = {
+      "command": "amm_info",
+      "asset": {
+        "currency": "XRP"
+      },
+      "asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      },
+      "ledger_index": "validated"
+    }
+
+  } else if (asset2_currency =='XRP') {
+
+    amm_info_request = {
+      "command": "amm_info",
+      "asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "asset2": {
+        "currency": "XRP"
+      },
+      "ledger_index": "validated"
+    }
+
+  } else {
+
+    amm_info_request = {
+      "command": "amm_info",
+      "asset": {
+        "currency": asset1_currency,
+        "issuer": asset1_issuer
+      },
+      "asset2": {
+        "currency": asset2_currency,
+        "issuer": asset2_issuer
+      },
+      "ledger_index": "validated"
+    }
+    
+  }
+```
+
+Submit the request in a `try-catch` block and update the AMM log.
+
+```javascript
+  try {
+    const amm_info_result = await client.request(amm_info_request)
+    ammInfo = `AMM Info:\n\n${JSON.stringify(amm_info_result.result.amm, null, 2)}`
+  } catch(error) {
+    ammInfo = `AMM Info:\n\n${error}`
+  }
+  
+  ammInfoField.value = ammInfo
+      
+  client.disconnect()
+  
+}
+```

docs/tutorials/javascript/amm/index.md

@@ -0,0 +1,12 @@
+---
+parent: modular-tutorials-in-javascript.html
+top_nav_grouping: Article Types
+metadata:
+  indexPage: true
+---
+# AMMs Using JavaScript
+
+Create and interact with Automated Market Makers (AMMs) on the XRP Ledger using JavaScript.
+
+
+{% child-pages /%}

docs/tutorials/javascript/amm/trade-with-auction-slot.md

@@ -0,0 +1,640 @@
+# Trade with an AMM Auction Slot
+
+Follow the steps from the [Create an AMM](/docs/tutorials/javascript/amm/create-an-amm/) tutorial before proceeding.
+
+This example shows how to:
+
+1. Calculate the exact cost of swapping one token for another in an AMM pool.
+2. Check the difference in trading fees with and without an auction slot.
+3. Bid on an auction slot with LP tokens.
+4. Create an offer to swap tokens with the AMM.
+
+[![Trade with Auction Slot Test Harness](/docs/img/quickstart-trade-auction-slot1.png)](/docs/img/quickstart-trade-auction-slot1.png)
+
+You can download the [Quickstart Samples](https://github.com/XRPLF/xrpl-dev-portal/tree/master/_code-samples/quickstart/js/)<!-- {.github-code-download} --> archive to try each of the samples in your own browser.
+
+{% admonition type="note" name="Note" %}
+Without the Quickstart Samples, you will not be able to try the examples that follow.
+{% /admonition %}
+
+
+## Usage
+
+### Get Accounts
+
+1. Open `13.trade-with-auction-slot.html` in a browser.
+2. Select **Testnet** or **Devnet**
+3. Get test accounts.
+   - If you have existing account seeds:
+     1. Paste account seeds in the **Seeds** field.
+     2. Click **Get Accounts from Seeds**.
+   - If you don't have account seeds:
+     1. Click **Get New Standby Account**.
+     2. Click **Get New Operational Account**.
+
+[![Get account results](/docs/img/quickstart-trade-auction-slot2.png)](/docs/img/quickstart-trade-auction-slot2.png)
+
+
+### Get the AMM
+
+Use the information from either the XRP/Token or Token/Token AMM you created in [Create an AMM](/docs/tutorials/javascript/amm/create-an-amm/#create-an-xrp/token-amm).
+
+1. Enter a [currency code](/docs/references/protocol/data-types/currency-formats.md#currency-codes) in the **Asset 1 Currency** field. For example, `XRP`.
+2. Enter a second currency code in the **Asset 2 Currency** field. For example, `TST`.
+3. Enter the operational account address in the **Asset 2 Issuer** field.
+4. Click **Check AMM**.
+
+[![Get AMM results](/docs/img/quickstart-trade-auction-slot3.png)](/docs/img/quickstart-trade-auction-slot3.png)
+
+
+### Estimate Costs
+
+Get a new standby account to ensure you aren't using an account with an auction slot already.
+
+1. Click **Get New Standby Account**.
+2. Under the **Taker Pays** column:
+   - Enter a currency code in the **Currency** field. For example, `TST`.
+   - Enter the operational account address in the **Issuer** field.
+   - Enter an **Amount**. For example, `10`.
+3. Under the **Taker Gets** column, enter a currency code in the **Currency** field. For example, `XRP`.
+4. Click **Estimate Cost**.
+5. Save the values given by the estimate.
+
+[![Estimate costs results](/docs/img/quickstart-trade-auction-slot4.png)](/docs/img/quickstart-trade-auction-slot4.png)
+
+
+### Bid for the Auction Slot
+
+Make a single-asset deposit to the AMM to receive the required LP tokens for the auction slot bid. You can deposit either asset from the cost estimator.
+
+1. Enter the estimated deposit amount in either **Asset 1 Amount** or **Asset 2 Amount**. For example, `0.004012` in **Asset 1 Amount**.
+2. Click **Add to AMM**.
+3. Enter the estimated bid amount in the **LP Tokens** field. For example, `6.326`.
+4. Click **Bid Auction Slot**.
+
+[![Bid auction slot results](/docs/img/quickstart-trade-auction-slot5.png)](/docs/img/quickstart-trade-auction-slot5.png)
+
+
+### Swap Tokens with the AMM
+
+Get a new estimate to update the expected cost for swapping tokens.
+
+1. Click **Estimate Cost**.
+2. Under the **Taker Gets Column**, enter an **Amount**. Use the expected cost with an auction slot from the estimate. For example, `1.112113`.
+3. Click **Swap Tokens**.
+
+[![Swap tokens with AMM results](/docs/img/quickstart-trade-auction-slot6.png)](/docs/img/quickstart-trade-auction-slot6.png)
+
+
+## Code Walkthrough (ripplex13a-trade-with-auction-slot.js)
+
+You can open `ripplex13a-trade-with-auction-slot.js` from the [Quickstart Samples](https://github.com/XRPLF/xrpl-dev-portal/tree/master/_code-samples/quickstart/js/) to view the source code.
+
+
+### Estimate AMM Costs
+
+This function checks the cost of interactions with the AMM, such as deposits, auction slot bids, and token swaps.
+
+```javascript
+async function estimateCost() {
+```
+
+Connect to the XRP Ledger.
+
+```javascript
+    let net = getNet()
+
+    const client = new xrpl.Client(net)
+    results = `\n\nConnecting to ${getNet()} ...`
+    standbyResultField.value = results
+
+    await client.connect()
+    results += '\n\nConnected.'
+    standbyResultField.value = results
+```
+
+Format the `amm_info` command and get the AMM information. This code is wrapped in a `try-catch` block to handle any errors.
+
+```javascript
+    try {
+
+        const asset1_currency = asset1CurrencyField.value
+        const asset1_issuer = asset1IssuerField.value
+
+        const asset2_currency = asset2CurrencyField.value
+        const asset2_issuer = asset2IssuerField.value
+
+
+        // Look up AMM info
+
+        let asset1_info = null
+        let asset2_info = null
+
+        if ( asset1_currency == 'XRP' ) {
+            asset1_info = {
+                "currency": "XRP"
+            }
+        } else {
+            asset1_info = {
+                "currency": asset1_currency,
+                "issuer": asset1_issuer
+            }
+        }
+
+        if ( asset2_currency == 'XRP' ) {
+            asset2_info = {
+                "currency": "XRP"
+            }
+        } else {
+            asset2_info = {
+                "currency": asset2_currency,
+                "issuer": asset2_issuer
+            }
+        }
+
+        const amm_info = (await client.request({
+            "command": "amm_info", 
+            "asset": asset1_info,
+            "asset2": asset2_info
+        }))
+
+        // Save relevant AMM info for calculations
+
+        const lpt = amm_info.result.amm.lp_token
+        const pool_asset1 = amm_info.result.amm.amount
+        const pool_asset2 = amm_info.result.amm.amount2
+        const full_trading_fee = amm_info.result.amm.trading_fee
+        const discounted_fee = amm_info.result.amm.auction_slot.discounted_fee
+        const old_bid = amm_info.result.amm.auction_slot.price.value
+        const time_interval = amm_info.result.amm.auction_slot.time_interval
+
+        results += `\n\nTrading Fee: ${full_trading_fee/1000}%\nDiscounted Fee: ${discounted_fee/1000}%`
+```
+
+Save the taker pays and taker gets fields; use these values to get the total amount of each asset in the AMM pool, using large significant digits for precise calculations. This also checks if the requested token amount is larger than what is available in the AMM pool, stopping the code if `true`.
+
+```javascript
+        // Save taker pays and gets values.
+        
+        const takerPays = {
+            "currency": standbyTakerPaysCurrencyField.value,
+            "issuer": standbyTakerPaysIssuerField.value,
+            "amount": standbyTakerPaysAmountField.value
+        }
+
+        const takerGets = {
+            "currency": standbyTakerGetsCurrencyField.value,
+            "issuer": standbyTakerGetsIssuerField.value,
+            "amount": standbyTakerGetsAmountField.value
+        }
+
+        // Get amount of assets in the pool.
+        // Convert values to BigNumbers with the appropriate precision.
+        // Tokens always have 15 significant digits;
+        // XRP is precise to integer drops, which can be as high as 10^17
+
+        let asset_out_bn = null
+        let pool_in_bn = null
+        let pool_out_bn = null
+        let isAmmAsset1Xrp = false
+        let isAmmAsset2Xrp = false
+
+        if ( takerPays.currency == 'XRP' ) {
+            asset_out_bn = BigNumber(xrpl.xrpToDrops(takerPays.amount)).precision(17)
+        } else {
+            asset_out_bn = BigNumber(takerPays.amount).precision(15)
+        }
+
+        if ( takerGets.currency == 'XRP' && asset1_currency == 'XRP' ) {
+            pool_in_bn = BigNumber(pool_asset1).precision(17)
+            isAmmAsset1Xrp = true
+        } else if ( takerGets.currency == 'XRP' && asset2_currency == 'XRP' ) {
+            pool_in_bn = BigNumber(pool_asset2).precision(17)
+            isAmmAsset2Xrp = true
+        } else if ( takerGets.currency == asset1_currency ) {
+            pool_in_bn = BigNumber(pool_asset1.value).precision(15)
+        } else {
+            pool_in_bn = BigNumber(pool_asset2.value).precision(15)
+        }
+
+        if (takerPays.currency == 'XRP' && asset1_currency == 'XRP' ) {
+            pool_out_bn = BigNumber(pool_asset1).precision(17)
+        } else if ( takerPays.currency == 'XRP' && asset2_currency == 'XRP' ) {
+            pool_out_bn = BigNumber(pool_asset2).precision(17)
+        } else if ( takerPays.currency == asset1_currency ) {
+            pool_out_bn = BigNumber(pool_asset1.value).precision(15)
+        } else {
+            pool_out_bn = BigNumber(pool_asset2.value).precision(15)
+        }
+
+        if ( takerPays.currency == 'XRP' && parseFloat(takerPays.amount) > parseFloat(xrpl.dropsToXrp(pool_out_bn)) ) {
+            results += `\n\nRequested ${takerPays.amount} ${takerPays.currency}, but AMM only holds ${xrpl.dropsToXrp(pool_out_bn)}. Quitting.`
+            standbyResultField.value = results
+            client.disconnect()
+            return
+        } else if ( parseFloat(takerPays.amount) > parseFloat(pool_out_bn) ) {
+            results += `\n\nRequested ${takerPays.amount} ${takerPays.currency}, but AMM only holds ${pool_out_bn}. Quitting.`
+            standbyResultField.value = results
+            client.disconnect()
+            return
+        }
+```
+
+Use [AMM helper functions](https://github.com/XRPLF/rippled/blob/2d1854f354ff8bb2b5671fd51252c5acd837c433/src/ripple/app/misc/impl/AMMHelpers.cpp) to estimate values for:
+
+- Cost to swap token without an auction slot.
+- Cost to swap token with an auction slot.
+- LP tokens to win an auction slot. This value factors the increase in the minimum bid of having new LP tokens issued to you from your deposit.
+- The amount of tokens for single-asset deposits to get the required LP tokens to win the auction slot.
+
+```javascript
+        // Use AMM's SwapOut formula to figure out how much of the takerGets asset
+        // you have to pay to receive the target amount of takerPays asset
+        const unrounded_amount = swapOut(asset_out_bn, pool_in_bn, pool_out_bn, full_trading_fee)
+        // Drop decimal places and round ceiling to ensure you pay in enough.
+        const swap_amount = unrounded_amount.dp(0, BigNumber.ROUND_CEIL)
+
+        // Helper function to convert drops to XRP in log window
+        function convert(currency, amount) {
+            if ( currency == 'XRP' ) {
+                amount = xrpl.dropsToXrp(amount)
+            }
+            return amount
+        }
+
+        results += `\n\nExpected cost for ${takerPays.amount} ${takerPays.currency}: ${convert(takerGets.currency, swap_amount)} ${takerGets.currency}`
+
+        // Use SwapOut to calculate discounted swap amount with auction slot
+        const raw_discounted = swapOut(asset_out_bn, pool_in_bn, pool_out_bn, discounted_fee)
+        const discounted_swap_amount = raw_discounted.dp(0, BigNumber.ROUND_CEIL)    
+        results += `\n\nExpected cost with auction slot for ${takerPays.amount} ${takerPays.currency}: ${convert(takerGets.currency, discounted_swap_amount)} ${takerGets.currency}`
+
+        // Calculate savings by using auction slot
+        const potential_savings = swap_amount.minus(discounted_swap_amount)
+        results += `\nPotential savings: ${convert(takerGets.currency, potential_savings)} ${takerGets.currency}`
+
+        // Calculate the cost of winning the auction slot, in LP Tokens.
+        const auction_price = auctionDeposit(old_bid, time_interval, full_trading_fee, lpt.value).dp(3, BigNumber.ROUND_CEIL)
+        results += `\n\nYou can win the current auction slot by bidding ${auction_price} LP Tokens.`
+
+        // Calculate how much to add for a single-asset deposit to receive the target LP Token amount
+        let deposit_for_bid_asset1 = null
+        let deposit_for_bid_asset2 = null
+
+        if ( isAmmAsset1Xrp == true ) {
+            deposit_for_bid_asset1 = xrpl.dropsToXrp(ammAssetIn(pool_asset1, lpt.value, auction_price, full_trading_fee).dp(0, BigNumber.ROUND_CEIL))
+        } else {
+            deposit_for_bid_asset1 = ammAssetIn(pool_asset1.value, lpt.value, auction_price, full_trading_fee).dp(15, BigNumber.ROUND_CEIL)
+        }
+
+        if ( isAmmAsset2Xrp == true ) {
+            deposit_for_bid_asset2 = xrpl.dropsToXrp(ammAssetIn(pool_asset2, lpt.value, auction_price, full_trading_fee).dp(0, BigNumber.ROUND_CEIL))
+        } else {
+            deposit_for_bid_asset2 = ammAssetIn(pool_asset2.value, lpt.value, auction_price, full_trading_fee).dp(15, BigNumber.ROUND_CEIL)
+        }
+
+        if ( isAmmAsset1Xrp == true ) {
+            results += `\n\nMake a single-asset deposit to the AMM of ${deposit_for_bid_asset1} XRP or ${deposit_for_bid_asset2} ${pool_asset2.currency} to get the required LP Tokens.`
+        } else if ( isAmmAsset2Xrp == true ) {
+            results += `\n\nMake a single-asset deposit to the AMM of ${deposit_for_bid_asset1} ${pool_asset1.currency} or ${deposit_for_bid_asset2} XRP to get the required LP Tokens.`
+        } else {
+            results += `\n\nMake a single-asset deposit to the AMM of ${deposit_for_bid_asset1} ${pool_asset1.currency} or ${deposit_for_bid_asset2} ${pool_asset2.currency} to get the required LP Tokens.`
+        }
+
+    } catch (error) {
+        results += `\n\n${error.message}`
+    }
+```
+
+Report the estimated values and close the client connection.
+
+```javascript
+    standbyResultField.value = results
+
+    client.disconnect()
+
+}
+```
+
+
+### Bid on the Auction Slot
+
+This function bids on the AMM auction slot, using LP tokens.
+
+```javascript
+async function bidAuction() {
+```
+
+Connect to the ledger.
+
+```javascript
+    let net = getNet()
+
+    const client = new xrpl.Client(net)
+    results = `\n\nConnecting to ${getNet()} ...`
+    standbyResultField.value = results
+
+    await client.connect()
+    results += '\n\nConnected.'
+    standbyResultField.value = results
+```
+
+Format the asset values, depending on if it's `XRP` or a token. Wrap the code in a `try-catch` block to handle any errors.
+
+```javascript
+    try {
+
+        const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
+
+        const asset1_currency = asset1CurrencyField.value
+        const asset1_issuer = asset1IssuerField.value
+
+        const asset2_currency = asset2CurrencyField.value
+        const asset2_issuer = asset2IssuerField.value
+        const valueLPT = standbyLPField.value
+
+        // Look up AMM info
+
+        let asset1_info = null
+        let asset2_info = null
+
+        if ( asset1_currency == 'XRP' ) {
+            asset1_info = {
+                "currency": "XRP"
+            }
+        } else {
+            asset1_info = {
+                "currency": asset1_currency,
+                "issuer": asset1_issuer
+            }
+        }
+
+        if ( asset2_currency == 'XRP' ) {
+            asset2_info = {
+                "currency": "XRP"
+            }
+        } else {
+            asset2_info = {
+                "currency": asset2_currency,
+                "issuer": asset2_issuer
+            }
+        }
+
+        const amm_info = (await client.request({
+            "command": "amm_info", 
+            "asset": asset1_info,
+            "asset2": asset2_info
+        }))
+
+        // Save relevant AMM info for calculations
+
+        const lpt = amm_info.result.amm.lp_token
+
+        results += '\n\nBidding on auction slot ...'
+        standbyResultField.value = results
+```
+
+Submit the `AMMBid` transaction.
+
+```javascript
+        const bid_result = await client.submitAndWait({
+            "TransactionType": "AMMBid",
+            "Account": standby_wallet.address,
+            "Asset": asset1_info,
+            "Asset2": asset2_info,
+            "BidMax": {
+                "currency": lpt.currency,
+                "issuer": lpt.issuer,
+                "value": valueLPT
+            },
+            "BidMin": {
+                "currency": lpt.currency,
+                "issuer": lpt.issuer,
+                "value": valueLPT
+            } // So rounding doesn't leave dust amounts of LPT
+            }, {autofill: true, wallet: standby_wallet})
+    
+        if (bid_result.result.meta.TransactionResult == "tesSUCCESS") {
+            results += `\n\nTransaction succeeded.`
+            checkAMM()
+        } else {
+            results += `\n\nError sending transaction: ${JSON.stringify(bid_result.result.meta.TransactionResult, null, 2)}`
+        }        
+    } catch (error) {
+        results += `\n\n${error.message}`
+    }
+```
+
+Report the results.
+
+```javascript
+    standbyResultField.value = results
+
+    client.disconnect()
+
+}
+```
+
+
+### Swap AMM Tokens
+
+This function submits an `OfferCreate` transaction, using precise values to format the transaction and have the AMM completely consume the offer.
+
+```javascript
+async function swapTokens() {
+```
+
+Connect to the XRP Ledger.
+
+```javascript
+    let net = getNet()
+
+    const client = new xrpl.Client(net)
+    results = `\n\nConnecting to ${getNet()} ...`
+    standbyResultField.value = results
+
+    await client.connect()
+    results += '\n\nConnected.'
+    standbyResultField.value = results
+```
+
+Get the taker pays and taker gets fields and format the amounts depending on if it's `XRP` or a custom token. Wrap the code in a `try-catch` block to handle any errors.
+
+```javascript
+    try {
+
+        const standby_wallet = xrpl.Wallet.fromSeed(standbySeedField.value)
+
+        const takerPaysCurrency = standbyTakerPaysCurrencyField.value
+        const takerPaysIssuer = standbyTakerPaysIssuerField.value
+        const takerPaysAmount = standbyTakerPaysAmountField.value
+
+        const takerGetsCurrency = standbyTakerGetsCurrencyField.value
+        const takerGetsIssuer = standbyTakerGetsIssuerField.value
+        const takerGetsAmount = standbyTakerGetsAmountField.value
+
+        let takerPays = null
+        let takerGets = null
+
+        if ( takerPaysCurrency == 'XRP' ) {
+            takerPays = xrpl.xrpToDrops(takerPaysAmount)
+        } else {
+            takerPays = {
+                "currency": takerPaysCurrency,
+                "issuer": takerPaysIssuer,
+                "value": takerPaysAmount
+            }
+        }
+
+        if ( takerGetsCurrency == 'XRP' ) {
+            takerGets = xrpl.xrpToDrops(takerGetsAmount)
+        } else {
+            takerGets = {
+                "currency": takerGetsCurrency,
+                "issuer": takerGetsIssuer,
+                "value": takerGetsAmount
+            }
+        }
+
+        results += '\n\nSwapping tokens ...'
+        standbyResultField.value = results
+```
+
+Submit the `OfferCreate` transaction.
+
+```javascript
+        const offer_result = await client.submitAndWait({
+            "TransactionType": "OfferCreate",
+            "Account": standby_wallet.address,
+            "TakerPays": takerPays,
+            "TakerGets": takerGets
+        }, {autofill: true, wallet: standby_wallet})
+        
+        if (offer_result.result.meta.TransactionResult == "tesSUCCESS") {
+            results += `\n\nTransaction succeeded.`
+            checkAMM()
+        } else {
+            results += `\n\nError sending transaction: ${JSON.stringify(offer_result.result.meta.TransactionResult, null, 2)}`
+        }        
+    } catch (error) {
+        results += `\n\n${error.message}`
+    }
+```
+
+Report the results.
+
+```javascript
+    standbyResultField.value = results
+
+    client.disconnect()
+
+}
+```
+
+
+## Code Walkthrough (ripplex13b-amm-formulas.js) 
+
+You can open `ripplex13b-amm-formulas.js` from the [Quickstart Samples](https://github.com/XRPLF/xrpl-dev-portal/tree/master/_code-samples/quickstart/js/) to view the source code. This tutorial uses three of the available [AMM helper functions](https://github.com/XRPLF/rippled/blob/2d1854f354ff8bb2b5671fd51252c5acd837c433/src/ripple/app/misc/impl/AMMHelpers.cpp).
+
+
+### swapOut()
+
+The `swapOut()` function calculates how much of an asset you must deposit into an AMM to receive a specified amount of the paired asset. The input asset is what you're adding to the pool (paying), and the output asset is what you're receiving from the pool (buying).
+
+The formula used is based on [AMM Swap](https://github.com/XRPLF/XRPL-Standards/tree/master/XLS-0030-automated-market-maker#25-amm-swap), defined in XLS-30.
+
+| Parameter | Type | Description |
+|-----------|------|-------------|
+| asset_out_bn | BigNumber | The target amount to receive from the AMM. |
+| pool_in_bn | BigNumber | The amount of the input asset in the AMM's pool before the swap. |
+| pool_out_bn | BigNumber | The amount of the output asset in the AMM's pool before the swap. |
+| trading_fee | int | The trading fee as an integer {0, 1000} where 1000 represents a 1% fee. |
+
+| Returns | Type | Description |
+|---------|------|-------------|
+| Return Value | BigNumber | The amount of the input asset that must be swapped in to receive the target output amount. Unrounded, because the number of decimals depends on if this is drops of XRP or a decimal amount of a token; since this is a theoretical input to the pool, it should be rounded up (ceiling) to preserve the pool's constant product. |
+
+```javascript
+function swapOut(asset_out_bn, pool_in_bn, pool_out_bn, trading_fee) {
+    return ( ( pool_in_bn.multipliedBy(pool_out_bn) ).dividedBy(
+                pool_out_bn.minus(asset_out_bn)
+             ).minus(pool_in_bn)
+           ).dividedBy(feeMult(trading_fee))
+}
+```
+
+### auctionDeposit()
+
+The `auctionDeposit()` calculates how many LP tokens you need to spend to win the auction slot. The formula assumes you don't have any LP tokens and factors in the increase in LP tokens issued when you deposit assets. If you already have LP tokens, you can use the `auctionPrice()` function instead.
+
+The formula used is based on the [slot pricing algorithm](https://github.com/XRPLF/XRPL-Standards/tree/master/XLS-0030-automated-market-maker#411-slot-pricing) defined in XLS-30.
+
+```javascript
+function auctionDeposit(old_bid, time_interval, trading_fee, lpt_balance) {
+    const tfee_decimal = feeDecimal(trading_fee)
+    const lptokens = BigNumber(lpt_balance)
+    const b = BigNumber(old_bid)
+    let outbidAmount = BigNumber(0) // This is the case if time_interval >= 20
+    if (time_interval == 0) {
+        outbidAmount = b.multipliedBy("1.05")
+    } else if (time_interval <= 19) {
+        const t60 = BigNumber(time_interval).multipliedBy("0.05").exponentiatedBy(60)
+        outbidAmount = b.multipliedBy("1.05").multipliedBy(BigNumber(1).minus(t60))
+    }
+
+    const new_bid = lptokens.plus(outbidAmount).dividedBy(
+                            BigNumber(25).dividedBy(tfee_decimal).minus(1)
+                          ).plus(outbidAmount)
+    
+    // Significant digits for the deposit are limited by total LPTokens issued
+    // so we calculate lptokens + deposit - lptokens to determine where the
+    // rounding occurs. We use ceiling/floor to make sure the amount we receive
+    // after rounding is still enough to win the auction slot.
+    const rounded_bid = new_bid.plus(lptokens).precision(15, BigNumber.CEILING
+                              ).minus(lptokens).precision(15, BigNumber.FLOOR)
+    return rounded_bid
+}
+```
+
+### ammAssetIn()
+
+The `ammAssetIn()` function calculates how much to add in a single-asset deposit to receive a specified amount of LP tokens.
+
+| Parameter | Type | Description |
+|-----------|------|-------------|
+| pool_in | string | The quantity of the input asset the pool already has. |
+| lpt_balance | string | The quantity of LP tokens already issued by the AMM. |
+| desired_lpt | string | The quantity of new LP tokens you want to receive. |
+| trading_fee | int | The trading fee as an integer {0, 1000} where 1000 represents a 1% fee. |
+
+```javascript
+function ammAssetIn(pool_in, lpt_balance, desired_lpt, trading_fee) {
+    // convert inputs to BigNumber
+    const lpTokens = BigNumber(desired_lpt)
+    const lptAMMBalance = BigNumber(lpt_balance)
+    const asset1Balance = BigNumber(pool_in)
+
+    const f1 = feeMult(trading_fee)
+    const f2 = feeMultHalf(trading_fee).dividedBy(f1)
+    const t1 = lpTokens.dividedBy(lptAMMBalance)
+    const t2 = t1.plus(1)
+    const d = f2.minus( t1.dividedBy(t2) )
+    const a = BigNumber(1).dividedBy( t2.multipliedBy(t2))
+    const b = BigNumber(2).multipliedBy(d).dividedBy(t2).minus( 
+                    BigNumber(1).dividedBy(f1)
+              )
+    const c = d.multipliedBy(d).minus( f2.multipliedBy(f2) )
+    return asset1Balance.multipliedBy(solveQuadraticEq(a,b,c))
+}
+```
+
+Compute the quadratic formula. This is a helper function for `ammAssetIn()`. Parameters and return value are `BigNumber` instances.
+
+```javascript
+function solveQuadraticEq(a,b,c) {
+    const b2minus4ac = b.multipliedBy(b).minus( 
+                            a.multipliedBy(c).multipliedBy(4) 
+                       )
+    return ( b.negated().plus(b2minus4ac.sqrt()) ).dividedBy(a.multipliedBy(2))
+}
+```