Subtle differences between assignment and mutation in Julia as shown in the script below are easy to be missed or misunderstood by a beginner like me. I’m starting to understand and realize the importance, but still not really confident. If there’s a good (clear, plain, accurate and concise) documen…

The simplest version of this I can come up with is this: Assignment changes which object a name refers to: x = ex causes the name x to refer to the value resulting from the evaluation of the expression ex. Assignment never changes the values of any objects. Mutation changes the value of an obj…

Maybe this is a good read: Values vs. Bindings: The Map is Not the Territory · John Myles White

Thanks for the pointer. I needed to know how to make sure an array in a function was mutating, not copying when I used it thousands of times repeatedly. Because copying increases allocation and tons of garbage collection tend to make it slow.

Thank you for a nice and helpful explanation. The meaning of “=” is indeed ambiguous sometimes, not only in programming languages, but also in mathematics. Even “abused” in a sense… In R, “<-” is used for assignment. So, an operation like temp(a ← a + 1) is possible. In Julia, temp(a = a + 1) has …

[image] suiato: The difference is just a dot There is a trade-off between keeping the syntax convenient and clearly demarcating various semantics. In a sense, .= extends the broadcasting syntax naturally to assignment. I think you may find it neat when you get used to it, but if you carry ov…

Assignment and mutation

New to Julia

rdeits December 30, 2018, 4:32pm 3

Perhaps this will help as well: Primitive and Composite? Types - #7 by rdeits

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Assignment and mutation

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