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hwers

what does 1-based mean?

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The first element of the array is A[1], rather than A[0] like it would be in nearly all programming languages.

There is of course the compromise position of 0.5.

I prefer 9. It makes no less sense than 1, but it is conveniently much closer to the + and - keys.

My 0 key is twice as big as the rest of the digits.

https://www.realtimerendering.com/blog/the-center-of-the-pix...

Huh. I thought it was obvious: e.g., the top-left corner of the screen is (0, 0), the bottom-right corner is (640, 480), and pixels are 1x1 — we take the coordinate of their top-left corner to be their coordinate, so the top-left pixel has coordinates (0, 0), and the bottom-right one has (639, 479), and obviously the coordinates of their centres are (0.5, 0.5) and (639.5, 479.5).

But apparently some people treated pixels as geometrical points without size?

It's normal in signal processing to treat samples (whether audio or image) as points. A lot of things stop making sense if you replace them with line segments and rectangles.

Which is rounded down to 0 or up to 1 at random.

Why compromise? Just have a helpful variable like Perl's $[ to set the first element index.

Nearly all meaning the non-scientific computing ones, and particularly the ones with syntax inspired by C. Fortran, APL, Matlab, Wolfram, Mathematica, R, Julia, Cobol, Smalltalk and Lua are all 1-based, at least by default.

Or maybe not so much inspired by C, but inspired by similar arguments as Dijkstra makes in his "Why numbering should start at zero": https://www.cs.utexas.edu/users/EWD/transcriptions/EWD08xx/E....

The array indexes start at 1, not 0.

It's entries are A[1], A[2],...,A[n] instead of A[0], A[1],...,A[n-1].

It means you probably shouldn't be on Hackernews

It means they should definitely be on HN where they're very likely to learn new things.

Welcoming open, thoughtful discussion and having people much smarter and with more experience than myself available to answer questions in which I'm not an expert is one of the main reasons I frequent HN.

> too young to know FORTRAN.

If you don't know, you don't know.

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