Comment on Explain yourselves, comp sci.

• ipha@lemm.ee ⁨11⁩ ⁨months⁩ ago

  It’s like a fancy list.

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  • fossilesque@mander.xyz ⁨11⁩ ⁨months⁩ ago

    So is a wedding gift registry.

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    • whereBeWaldo@lemmy.dbzer0.com ⁨11⁩ ⁨months⁩ ago

      No this is Patrick!

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• Fosheze@lemmy.world ⁨11⁩ ⁨months⁩ ago

  It’s a dynamically-sized list of objects of the same type stored contiguously in memory.

  dynamically-sized: The size of it can change as needed.

  list: It stores multiple things together.

  object: A bit of programmer defined data with.

  of the same type: all the objects in the list are the same kind of object

  stored contigiously in memory: if you think of memory as a bookshelf then all the objects on the list would be stored right next to each other on the bookshelf rather than spread across the bookshelf.

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  • kbotc@lemmy.world ⁨11⁩ ⁨months⁩ ago

    Dynamically sized but stored contiguously makes the systems performance engineer in me weep. If the lists get big, the kernel is going to do so much churn.

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    • Killing_Spark@feddit.de ⁨11⁩ ⁨months⁩ ago

      Contiguous storage is very fast in terms of iteration though often offsetting the cost of allocation

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      • Slotos@feddit.nl ⁨11⁩ ⁨months⁩ ago

        Modern CPUs are also extremely efficient at dealing with contiguous data structures. Branch prediction and caching get to shine on them.

        Avoiding memory access or helping CPU access it all upfront switches physical domain of computation.

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    • IAmVeraGoodAtThis@lemmy.blahaj.zone ⁨11⁩ ⁨months⁩ ago

      Which is why you should:

      1. Preallocate the vector if you can guesstimate the size
      2. Use a vector library that won’t reallocate the entire vector on every single addition (like Rust, whose Vec doubles in size every time it runs out of space)

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    • yetiftw@lemmy.world ⁨11⁩ ⁨months⁩ ago

      matlab likes to pick the smallest available spot in memory to store a list, so for loops that increase the size of a matrix it’s recommended to preallocate the space using a matrix full of zeros!

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    • tamal3@lemmy.world ⁨11⁩ ⁨months⁩ ago

      Is that churn or chum? (RN or M)

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      • Khanzarate@lemmy.world ⁨11⁩ ⁨months⁩ ago

        Churm

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• SpaceNoodle@lemmy.world ⁨11⁩ ⁨months⁩ ago

  Many things like each other lined up in a row, and you can take some away or put more in.

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• mindbleach@sh.itjust.works ⁨11⁩ ⁨months⁩ ago

  It’s how you want an array to work.

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