indexes与indices均为index的复数形式。
“Indices” is originally a Latin plural, while “Indexes” has taken the English way of making plurals, using –s or –es. Though both are still widely used, they take on different usage in their senses. “Indices” is used when referring to mathematical, scientific and statistical contexts. It is used to refer to a numbers, symbols, and figures comparing a value to a standard. “Indexes” is usually used in reference to written documents, such as bibliographical or citation listings.
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outlet：出口的意思
