Tick Size
Requires the TickSize amendment.
When an Offer is placed into an order book, its exchange rate is truncated based on the TickSize values set by the issuers of the currencies involved in the Offer. When a trader offers to exchange XRP and an issued currency, the TickSize from the issuer of the currency applies. When a trader offers to exchange two issued currencies, the offer uses the smaller TickSize value (that is, the one with fewer significant digits). If neither currency has a TickSize set, the default behavior applies.
当一个报价单放入一个order book时，其汇率将按照货币发行人所设置的TickSize而截断位数（匹配精度）。当交易者在一个报价单中进行XRP和已发行货币见兑换时，适用由该货币发行人设置的TickSize设置。当交易者在一个报价单中进行两种已发行货币的兑换时，报价单使用较小TickSize的值（即具有更少位数的那个）。如果两种货币对应发行人的TickSize设置相同，则默认适用。
The TickSize value truncates the number of significant digits in the exchange rate of an offer when it gets placed in an order book. Issuers can set TickSize to an integer from 3 to 15 using an AccountSet transaction. The exchange rate is represented as significant digits and an exponent; the TickSize does not affect the exponent. This allows the XRP Ledger to represent exchange rates between assets that vary greatly in value (for example, a hyperinflated currency compared to a rare commodity). The lower the TickSize an issuer sets, the larger the increment traders must offer to be considered a higher exchange rate than the existing Offers.
在order book中的报价单，会受TickSize设置而截断交易汇率中的有效位数。发行人可以使用AccountSet交易类型设置3-15位整数长度的TickSize设置值（精度）。汇率表示为有效数字和指数，TickSize设置不影响指数。这允许XRP总账网络在两个差异化资产价值之间提供汇率（例如通涨货币和稀缺商品之间）。发行人设置的TickSize越小， 越多的交易商就会考虑比当前已存在报价单更高的汇率的报价单。
The TickSize does not affect the part of an Offer that can be executed immediately. (For that reason, OfferCreate transactions with tfImmediateOrCancel are unaffected by TickSize values.) If the Offer cannot be fully executed, the transaction processing engine calculates the exchange rate and truncates it based on TickSize. Then, the engine rounds the remaining amount of the Offer from the “less important” side to match the truncated exchange rate. For a default OfferCreate transaction (a “buy” Offer), the TakerPays amount (the amount being bought) gets rounded. If the tfSell flag is enabled (a “sell” Offer) the TakerGets amount (the amount being sold) gets rounded.
TickSize设置不会影响报价单中能够立即执行的部分。（OfferCreate交易中开启tfImmediateOrCancel标志的不受tickSize设置影响。）如果报价单不能被完整执行，交易处理引擎会计算汇率并基于TickSize设置截断位数。然后，引擎将来自“不太重要”一侧的剩余额度进行汇率截断。例如典型交易OfferCreate（买入报价），其中TakerPays额度将被舍入。如果tfSell标志启用（卖出报价），则TakerGets额度将被舍入。
When an issuer enables, disables, or changes the TickSize, Offers that were placed under the previous setting are unaffected.
发行人启用，关闭，修改TickSize设置，以按照先前设置提交的报价单不受此部分行为影响。