Correct usage of "positive numbers" in FAQ section "What’s a negative index?". #140176
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I added the words `signed numbers` to cover zero, positive numbers and negative numbers in the section **What’s a negative index?**.
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| index and so forth. Think of ``seq[-n]`` as the same as ``seq[len(seq)-n]``. | ||
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| Using negative indices can be very convenient. For example ``S[:-1]`` is all of | ||
| Using negative indices can be very convenient. For example ``S[:-1]`` is all of |
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| positive numbers 0 is the first index 1 is the second index and so forth. For | ||
| negative indices -1 is the last index and -2 is the penultimate (next to last) | ||
| index and so forth. Think of ``seq[-n]`` as the same as ``seq[len(seq)-n]``. | ||
| Python sequences are indexed with signed numbers (zero, positive numbers and negative numbers). For example, 0 is the 1st index and for positive indices, 1 is the 2nd index, 2 is the 3rd index and so forth. For |
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CC @AA-Turner, I am interested to hear your opinion on this. |
StanFromIreland
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| Python sequences are indexed with signed numbers (zero, positive numbers and negative numbers). For example, 0 is the 1st index and for positive indices, 1 is the 2nd index, 2 is the 3rd index and so forth. For | ||
| negative indices, -1 is the last index, -2 is the penultimate (next to last) | ||
| index and so forth. Think of ``seq[-n]`` as the same as ``seq[len(seq)-n]``. |
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I don't think that old text was too bad. But you if considered to change that - please use more common terminology. What's "signed numbers" are? Integers, right?
You could mention that for non-negative indexes it's meaning is just usual zero-based indexing of arrays. For negative indexes, the index i is relative to the end of sequence, i.e.: len(seq) + i is substituted.
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I corrected the meaning of the words positive numbers used in the section What’s a negative index?.
In the original explanation, the words positive numbers are used to cover the numbers greater than or equal to zero but actually, zero is neither a positive number nor negative number. Positive numbers are only the numbers greater than zero.
So as the main change, I added the words signed numbers to cover 3 types of numbers zero, positive numbers and negative numbers in the section What’s a negative index?.
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