# Talk:Int64

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Jump to navigationJump to searchHigh(Int64)=9,223,372,036,854,775,807=(2^63)-1. Note the minus 1.

Also I think a closing bracket (]) is missing from the text inside the math markup? --Bart (talk) 23:10, 15 August 2020 (CEST)

- Err, no. It’s a half-open interval. It’s correct. Confer terminology for intervals. Kai Burghardt (talk) 07:47, 16 August 2020 (CEST)
- Well, that's why I said "I think". I suspect not may people really understand this math expression. — Preceding unsigned comment added by Bart (talk • contribs) 2020-08-16T13:04:01
- Ok, there was a question mark though. Anyway, you can say this about pretty much everything: What does “∩” mean? What is ℤ? What is 2
^{63}? It’s just, that’s basic stuff taught within the first four weeks of any college-level calculus course. And if you didn’t go to college, the written out numbers are given there, too. But feel free to change it. I prefer brevity. Kai Burghardt (talk) 21:03, 16 August 2020 (CEST)

- Ok, there was a question mark though. Anyway, you can say this about pretty much everything: What does “∩” mean? What is ℤ? What is 2

- Well, that's why I said "I think". I suspect not may people really understand this math expression. — Preceding unsigned comment added by Bart (talk • contribs) 2020-08-16T13:04:01

my 2 cents: My first idea was kind of: Isn't there a -1 missing somewhere? But I did not really think and care further about it. Sure enough, I did not get the detail about the two different brackets. Most likely, math courses are too long ago. The discussion above was actually the key to understand it. Even after understanding it and appreciating the brevity and elegance, I tend to favour the use of symmetric brackets, because it avoids the overlooking of the difference.

- In reply to above (unsigned) note by Mischi. It would the become [math]\displaystyle{ [-(2^{63}), 2^{63}-1)] \cap \mathbb{Z} }[/math]?? --Bart (talk) 13:24, 17 August 2020 (CEST)
- Now there is an extraneous right parenthesis. Maybe this is more understandable while still being correct: [math]\displaystyle{ \left\{n \in \mathbb{Z} \; \mid -\left(2^{63}\right) \leq n \lt 2^{63}\right\} }[/math] I think the lesser-than-or-equal-to sign is generally understood. Kai Burghardt (talk) 15:51, 17 August 2020 (CEST)