Note that the index variable ( {i in TOY} ) comes before the :.

注意索引变量（{i in TOY}）都是在 : 之前出现的。

youdao

Try to use a differently named index variable for each set consistently; it's a good idea, especially when debugging.

我们可以试图为每个集合使用不同的命名索引变量；这是一个好主意，尤其是在进行调试时更为突出。

youdao

The multimode waveguide area is one multimode interference area provided with two refractive index variable regions.

多模波导区是一个多模干涉区，其上设有两个折射率可改变的区域。

youdao

Well, the bracket notation means you can index into this variable.

好的，这个括号的意思是你可以,索引这个变量。

哈佛公开课 - 计算机科学课程节选

Now I seem to be violating my own mantra here by just calling this variable A, but this is reasonable, I much as with four loops when you just call an incrementing variable I, because you just need an index, well, same here.

现在我好像违背了我自己的意愿,我把这个变量叫做A，但这是合理的，就像我们的for循环中，我们把一个增变量叫做,因为我们只要一个索引，这里也一样。

哈佛公开课 - 计算机科学课程节选

Avoiding Google and Microsoft or at least underweighting them was the critical variable in gaming the tech index this year.

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Another critical variable in every stock market relates to which sectors dominate the capitalization of the index.

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But when taking the entire 500 stocks that make up the index as a whole, the multiple that is being applied as an average to all becomes less variable, although critical to assessing prices.

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