• NeatNit@discuss.tchncs.de
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    3 months ago

    The top symbol, Σ (uppercase Sigma), is used in math to denote a sum of a list of values. There is clear separation between the values in the list: two adjacent items in the list have no item in between them.

    The bottom symbol, ∫ (long s), denotes an integral, which is kind of a sum over a continuous function. Any two different points of the function, no matter how close they are to each other, will have infinitely many points in between them.

    For pedants: the function values don’t have to be continuous, but the range of x over which the integral runs does have to be continuous. I regret nothing.

    • itslilith@lemmy.blahaj.zone
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      3 months ago

      You can integrate over arbitrary domains, not even the range needs to be continuous. You often see integrals not written as \int_a^b, but instead as \int_C where C is just a set

    • thanks_shakey_snake@lemmy.ca
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      3 months ago

      Oh cool, thanks. So is this like an anti-aliasing joke or something? Like “if you discretize a small number of pixels, Rick Astley will appear pixelated, but if you interpolate between them, the image will appear clearer?”

      • NeatNit@discuss.tchncs.de
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        3 months ago

        Not quite, I think it means the source material is continuous instead of discrete. No interpolation.

        But honestly at this point we’re reading too much into it.

        • thanks_shakey_snake@lemmy.ca
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          3 months ago

          Oh that makes sense. It’s hard to get straight what the interpretation should be though because of course the higher-res image is also discrete, just more pixels.

          And like… Also why Rick Astley? I’m okay with “why not?” as the explanation there, but I feel like I’m missing something else there too.

          But honestly at this point we’re reading too much into it.

          Yes yes overanalyzing math memes is how I’m compensating for a poor high school experience.