Numbering of array indices in Julia

Question

I seem to find that I get an bounds error when I try to reference array[0]. So it seems that julia has elected to necessarily use the same convention that MATLAB uses, starting the indices from 1. Is this true? Any reason for that choice?

Answer 1

Yes, arrays are indexed from 1

Answer 2

Yes.

It is a not uncommon practice for languages to index their arrays starting 1. Check out Wikipedias page on Comparison of programming languages (array). Other notable languages that index from 1:

• Fortran
• Lua
• Mathematica
• MATLAB
• PL/1
• Smalltalk
• R

Note that half those examples are languages geared towards technical, statistical and scientific computing, just as Julia is.

When it comes to learning curve, indexing from 1 makes perfectly fine sense as the likely users will come from MATLAB, R, Fortran, et al which also index from 1.

Answer 3

According to a brief review on http://www.fortran90.org/src/faq.html#what-is-the-most-natural-starting-index-for-numbering, the most common starting index in math and science is 1, so it makes a sensible default.

Now there is experimental feature in Julia for offset array support http://docs.julialang.org/en/release-0.5/devdocs/offset-arrays/, so you may pick your own on array-per-array basis.