AMMWithdraw

[Source]

(Requires the AMM amendment)

Withdraw assets from an Automated Market Maker (AMM) instance by returning the AMM's liquidity provider tokens (LP Tokens).

Example AMMWithdraw JSON

{
    "Account" : "rJVUeRqDFNs2xqA7ncVE6ZoAhPUoaJJSQm",
    "Amount" : {
        "currency" : "TST",
        "issuer" : "rP9jPyP5kyvFRb6ZiRghAGw5u8SGAmU4bd",
        "value" : "5"
    },
    "Amount2" : "50000000",
    "Asset" : {
        "currency" : "TST",
        "issuer" : "rP9jPyP5kyvFRb6ZiRghAGw5u8SGAmU4bd"
    },
    "Asset2" : {
        "currency" : "XRP"
    },
    "Fee" : "10",
    "Flags" : 1048576,
    "Sequence" : 10,
    "TransactionType" : "AMMWithdraw"
}

AMMWithdraw Fields

In addition to the common fields, AMMWithdraw transactions use the following fields:

Note: For a double-asset withdrawal, it is possible for Asset to correspond to either Amount or Amount2 as long as Asset2 corresponds to the other one. It is recommended to match them (that is, Amount2 is an amount of the asset defined in Asset2) because it is less confusing that way.

AMMWithdraw Modes

This transaction has several modes, depending on which flags you specify. Each mode expects a specific combination of fields. The modes fall into two categories:

• Double-asset withdrawals, in which you receive both assets from the AMM's pool in proportions that match their balances there. These withdrawals are not subject to a fee.
• Single-asset withdrawals, in which you receive one asset from the AMM's pool. The AMM charges a fee based on how much your deposit shifts the balance of assets in the pool. Depending on the withdraw mode, the amount of the fee can be added to the amount of LP Tokens paid in, or debited from the amount of the asset paid out.

The following combinations of fields indicate a double-asset withdrawal:

The following combinations of fields indicate a single asset withdrawal:

Any other combination of these fields is invalid.

Single Asset Withdrawal Fee

The fee for a single asset withdrawal is calculated to be the same as if you had done a double-asset withdrawal and then used the AMM to trade all of the other asset for the one you are withdrawing. The trading fee applies to the amount you would need to trade for, but not to the rest of the withdrawal.

AMM Deletion

If the transaction withdraws the last of the AMM's assets, it automatically tries to delete the AMM along with all associated trust lines. However, there is a limit to how many empty trust lines can be removed in one transaction. If too many empty trust lines exist, the AMM remains in the ledger in an empty state; it can be deleted with further AMMDelete transactions, or it can be refilled with a special "empty AMM" two-asset AMMDeposit transaction. While an AMM is empty, no other operations on it are valid.

AMMWithdraw Flags

Transactions of the AMMWithdraw type support additional values in the Flags field, as follows:

You must specify exactly one of these flags, plus any global flags.

Error Cases

Besides errors that can occur for all transactions, AMMWithdraw transactions can result in the following transaction result codes: