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  • 25 Comments
Joined 11 months ago
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Cake day: July 22nd, 2023

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  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
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    edit-2
    7 months ago

    Just saw the image you posted and it's awesome :-) I'm part of the group that can't solve it, because I don't know the 🌭 function from the top of my head. I also found the choice of symbols interesting that 🌭 is analytical continuation of 🍔 and not the other way round 🤣



  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    7 months ago

    The calculator section is actually pretty important, because it shows how there is no consensus. Sharp is especially interesting with respect to your comment because all scientific Sharp calculators say it's 1. For all the other brands for hardware calculators there are roughly 50:50 with saying 1 and 9.

    So I'm not sure if you are suggesting that thousands of experts and hundreds of engineers at Casio, Texas Instruments, HP and Sharp got it wrong and you got it right?

    There really is no agreed upon standard even amongst experts.


  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    7 months ago

    I'm not sure if you read the post yet but I also have a short section about alternative notations which are less ambiguous or never ambiguous. RPN has the same issue as most notations that are never ambiguous namely that it's hard to read - especially for big expressions.


  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    edit-2
    7 months ago

    "when in doubt" is a bit broad but left to right is a great default for operations with the same priority. There is actually a way to calculate in any order if divisions are converted to multiplications (by using the reciprocal value) and subtractions are converted to additions (by negating the value) that requires at least a little bit of math knowledge and experience so it's typically not taught until later to prevent even more confusion.

    For example this: 6 / 2 * 3 can also be rewritten as 6 * 2⁻¹ * 3 and because multiplication is commutative you can now do it in any order for example like 3 * 6 * 2⁻¹

    You can also "rearrange" the order without changing the meaning if you move the correct operation (left to the number) with it (should only be done with explicit multiplication)

    6 / 2 * 3 into 6 * 3 / 2 (note that I moved the division with the 2)

    You can even bring the two to the front. Just remember that left to the six is an "imaginary" (don't quote me ^^) multiplication. And because we can't just move "/2" to the beginning we have to insert a one (empty product - check Wikipedia) like so:

    1 / 2 * 6 * 3

    This also works for addition and subtraction

    7 + 8 - 5

    You can move them around if you take the operation left to the number with it. With addition the "imaginary" operation at the beginning is a plus sign and the implicit number you use is zero (empty sum - check Wikipedia)

    8 - 5 + 7

    or like this

    0 - 5 + 8 + 7

    because with negative numbers you can use the minus sign to indicate negative numbers you can even drop the leading zero like this

    -5 + 8 + 7

    That's not really possible with multiplication because "/2" is not a valid notation for "1/2"


  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    7 months ago

    ❤️ True, but I think one of the biggest problems is that it's pretty long and because you can't really sense how good/bad/convining the text is it's always a gamble for everybody if it's worth reading something for 30min just to find out that the content is garbage.

    I hope I did a decent job in explaining the issue(s) but I'm definitely not mad if someone decides that they are not going to read the post and still comment about it.


  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    edit-2
    7 months ago

    The problem with BODMAS is that everybody is taught to remember "BODMAS" instead of "BO-DM-AS" or "BO(DM)(AS)". If you can't remember the order of operations by heart you won't remember that "DM" and "AS" are the same priority, that's why I suggested dropping "division" and "subtraction" entirely from the mnemonic.

    It's true that calculators also don't dictate a standard but they implement what conventions are typically used in practice. If a convention would be so dominating (let's say 95% vs 5%) all calculator manufacturers would just follow the 95% convention, except maybe for some very special-purpose calculators.


  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    7 months ago

    Now you changed it to an explicit multiplication. The ambiguity only comes from the implicit multiplication after a division, that's when the interpretation can be ambiguous. That's what the blog post really is about.


  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    7 months ago

    Thank you very much 🫶. No it's not annoying at all. I'm very grateful not only for the fact that you read the post but also that you took the time to point out issues.

    I just fixed it, should be live in a few minutes.


  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    7 months ago

    I'm not sure if I'd call it the "scientific" one. I'd actually say that the weak juxtaposition is just the simple one schools use because they don't want to confuse everyone. Scientist actually use both and make sure to prevent ambiguity. IMHO the main takeaway is that there is no consensus and one has to be careful to not write ambiguous expressions.



  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    edit-2
    7 months ago

    Thank you so much for taking the time. I'm also not convinced that APS's notation is a very good choice but I'm neither american nor a physisist 🤣

    I'd love to see how the exceptions work that the APS added, like allowing explicit multiplications on line-breaks, if they still would do the multiplication first, but I couldn't find a single instance where somebody following the APS notation had line-break inside an expression.


  • wischi@programming.dev
    hexagon
    toMemes@lemmy.ml6÷2(1+2)
    ·
    edit-2
    7 months ago

    True, and it's not only about learning math but that there is actually no consensus even amongst experts, about the priority of implicit multiplications (without explicit multiplication sign). In the blog post there are a lot of things that try to show why and how that's the case.







  • wischi@programming.devtoLinux@lemmy.mlThe future of Linux
    ·
    8 months ago

    Linux is way to fragmented and without a great dominating distro it will never. Waymand, Ubuntu, Mint, Gnome, KDE, WTF, Users don't fucking care about that jargon. Most Window users don't even know the name of the browser they are using or that "the internet app" is even called "browser".

    A few weeks ago I updated Ubuntu from 22 to 23 on my home media center. First tried the Updates App because why not just press a single fucking button like on windows or mac. No - no major updates there. Open a console, apt update and upgrade the hell out of everything, update the package sources with some shady regex command I copy pasted from some random forum, update upgrade again dist-upgrade WTF. After everything was done the layout of the info area (network, wifi, etc) was fucked up. Read some only shit about gnome shell extensions, themens, nothing made sense, force reinstalled the gome shell - worked again.

    And somebody expects that "typical" users to do that don't even know what Windows Version they are running - sure.