How to get a specific element from a list {a, b, c, d}?

Question

For example, I have x ={11,12,13,14}, how do I get the element staying at the third place, that is, 13?

You might want use Extract. For example Extract[3] @ x would extract the third element of list $x$. — LouisB, Jan 03 '22 at 23:12
Yes, and I expect there are many more ways to extract the nth element from the list! But the one with double square brackets is special because square brackets are commonly used to extract an element from a list or an array in programming languages but as a rule, other languages use ordinary square brackets for this purpose and this fact bewildered me and led to formulate my question here. — Errdonald, Jan 04 '22 at 20:40
So you're aware, the double square bracket notation is a shortcut for Part. — Carl Lange, Jan 04 '22 at 20:43

Errdonald · Answer 1 · 2022-01-04T07:10:28.907

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Use double square brackets to point at the element staying at the nth place, x[[3]] will produce the element staying in the third-place counting from 1 for the beginning of the list. In the example, it is 13. {11,12,13,14}[[1]] will produce 11 and {11,12,13,14}[[4]] equals Last[{11,12,13,14},that is, 14.

edited Jan 04 '22 at 07:10

answered Jan 03 '22 at 21:19

Errdonald

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This Q&A could (should?) go into What are the most common pitfalls awaiting new users? – user1066 Jan 05 '22 at 04:17
Sure, I visited the link and there is a discussion of double bracket access to the lists, thank you! – Errdonald Jan 05 '22 at 07:35

How to get a specific element from a list {a, b, c, d}?

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