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Joined 1 year ago
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Cake day: June 30th, 2023

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  • XDG specifies the capital names, but to be nitpickingly technically precise, linux systems don’t do this. It mostly is done by the distribution maintainers, and the XDG specs. A base system does not usually have a notion of anything beyond your $HOME.

    Try adding a user: sudo adduser basicuser. If you ls -al ~basicuser you will see it’s almost empty, just the .bashrc (or in my fedora, there’s some .mozilla crap in /etc/skel that also gets bootstrapped).



  • For bash, this is enough:

    # Bash TAB-completition enhancements
    # Case-insensitive
    bind "set completion-ignore-case on"
    # Treat - and _ as equivalent in tab-compl
    bind "set completion-map-case on"
    # Expand options on the _first_ TAB press.
    bind "set show-all-if-ambiguous on"
    

    If you also add e.g.CDPATH=~/Documents, it will also always autocomplete from your Documents no matter which directory you’re on.



  • Sure -> I’m not smart enough to explain it like you’re five, but maybe 12 or so would work?


    The problem

    The problem here is that you’re not adding 1 + 2, or 0.1 + 0.2. You’re converting those to binary (because computers talk binary), then you’re adding binary numbers, and converting the result back. And the error happens at this conversion step. Let’s take it slow, one thing at a time.


    decimal vs binary

    See, if you are looking at decimal numbers, it’s kinda like this:

    357 => 7 * 1 + 5 * 10 + 3 * 100. That sequence, from right to left, would be 1, 10, 100, … as you go from right to left, you keep multiplying that by 10.

    Binary is similar, except it’s not 1, 10, 100, 1000 but rather 1, 2, 4, 8, 16 -> multiply by 2 instead of 10. So for example:

    00101101 => right to left => 1 * 1 + 0 * 2 + 1 * 4 + 1 * 8 + 0 * 16 + 1 * 32 + 0 * 64 + 0 * 128 => 45

    The numbers 0, 1, 2, 3…9 we call digits (since we can represent each of them with one digit). And the binary “numbers” 0 and 1 we call bits.

    You can look up more at simple wikipedia links above probably.


    bits and bytes

    We usually “align” these so that we fill with zeroes on the left until some sane width, which we don’t do in decimal.

    132 is 132, right? But what if someone told you to write number 132 with 5 digits? We can just add zeroes. So call, “padding”.

    00132 - > it’s the same as 132.

    In computers, we often “align” things to 8 bits - or 8 places. Let’s say you have 5 - > 1001 in binary. To align it to 8 bits, we would add zeroes on the left, and write:

    00001001 -> 1001 -> decimal 5.

    Instead of, say, 100110, you would padd it to 8 bits, you can add two zeroes to left: 00100110.

    Think of it as a thousands separator - we would not write down a million dollars like this: $1000000. We would more frequently write it down like this: $1,000,000, right? (Europe and America do things differently with thousands- and fractions- separators, so 1,000.00 vs 1.000,00. Don’t ask me why.)

    So we group groups of three numbers usually, to have it easier to read large numbers.

    E.g. 8487173209478 is hard to read, but 8 487 173 209 478 is simpler to see, it’s eight and a half trillion, right?

    With binary, we group things into 8 bits - we call that “byte”. So we would often write this:

    01000101010001001010101010001101

    like this:

    01000101 01000100 10101010 10001101

    I will try to be using either 4 or 8 bits from now on, for binary.


    which system are we in?

    As a tangential side note, we sometimes add “b” or “d” in front of numbers, that way we know if it’s decimal or binary. E.g. is 100 binary or decimal?

    b100 vs d100 makes it easier. Although, we almost never use the d, but we do mark other systems that we use: b for binary, o for octal (system with 8 digits), h for hexadecimal (16 digits).

    Anyway.


    Conversion

    To convert numbers to binary, we’d take chunks out of it, write down the bit. Example:

    13 -> ?

    What we want to do is take chunks out of that 13 that we can write down in binary until nothing’s left.

    We go from the biggest binary value and substract it, then go to next and next until we get that 13 down to zero. Binary values are 1, 2, 4, 8, 16, 32, … (and we write them down as b0001, b0010, b0100, b1000, … with more zeroes on the left.)

    • the biggest of those that fit into 13 seems to be 8, or 1000. So let’s start there. Our binary numbers so far: 1000 And we have 13 - 8 = 5 left to deal with.

    • The biggest binary to fit into 5 is 4 (b0100). Our binary so far: b1000 + b0100 And our decimal leftover: 5 - 4 = 1.

    • The biggest binary to fit into 1 is 1 (b0001). So binary: b1000 + b0100 + b0001 And decimal: 1 - 1 = 0.

    So in the endl, we have to add these binary numbers:

    ` 1000 0100 +0001

    b1101 `

    So decimal 13 we write as 1101 in binary.


    Fractions

    So far, so good, right? Let’s go to fractions now. It’s very similar, but we split parts before and after the dot.

    E.g. 43.976 =>

    • the part before the dot (whole numbers part) -> 1 * 3 + 10 * 4 = > 13
    • the part after it (fractional part) -> 0.1 * 9 + 0.01 * 7 + 0.001 * 6
      Or, we could write it as: 9 / 10 + 7 / 100 + 6 / 1000.

    Just note that we started already with 10 on the fractional part, not with 1 (so it’s 1/10, 1/100, 1/1000…)

    The decimal part is similar, except instead of multiplying by 10, you divide by 10. It would be similar with binary: 1/2, 1/4, 1/8. Let’s try something:

    b0101.0110 ->

    • whole number part: 1 * 1 + 2 * 0 + 4 * 1 + 8 * 0 (5)
    • fractional part -> 0 / 2 + 1 / 4 + 1 / 8 + 0 / 16 -> 0.375.

    So b0101.0110 (in binary) would be 5.375 in decimal.


    Converting with fractions

    Now, let’s convert 2.5 into binary, shall we?

    First we take the whole part: 2. The biggest binary that fits is 2 (b0010). Now the fractional part, 0.5. What’s the biggest fraction we can write down? What are all of them?

    If you remember, it’s 1/2, 1/4, 1/8, 1/16… or in other words, 0.5, 0.25, 0.125, 0.0625…

    So 0.5 would be binary 1/2, or b0.1000

    And finally, 2.5 in decimal => b0010.1000

    Let’s try another one:

    13.625

    • Whole number part is 13 -> we already have it above, it’s b1101.
    • Fractional part: 0.625. The bigest fraction that fits is 0.5, or 1/2, or b0.1. We have then 0.625 - 0.5 = 0.125 left. The next fraction that fits is 1/8 (0.125), written as b0.0010.

    Together with b0.1000 above, it’s b0.1010 So the final number is:

    b1101.1010

    Get it? Try a few more:

    4.125, 9.0625, 13.75.

    Now, all these conversions so far, align very nicely. But what when they do not?


    Finaly, our problem.

    1 + 2 = 3. In binary, let’s padd it to 4 bits: 1 -> the biggest binary that fits is b0010. 2 -> the biggest thing that fits is b0010.

    b0001 + b0010 = b0011.

    If we convert the result back: b0011 -> to decimal, we get 3.

    Okay? Good.


    Now let’s try 0.1 + 0.2.

    • decimal 0.1 => 1 / 10.

    How do we get it in binary? Let’s find the biggest fraction that fits: 1/16, or 0.0625, or b0.0001 What’s left is 0.1 - 0.0625 = 0.0375. Next binary that fits: 1/32 or 0.03125 or b0.00001. We’re left with 0.00625. Next binary that fits is 1/256
    … etc etc until we get to:

    decimal 0.1 = b0.0001100110

    We can do the same with 0.2 -> b0.0011001100.

    Now, let’s add those two:

    ` b0.0001 1001 10 +b0.0011 0011 00

    b0.0100 1100 10 `

    Right? So far so good. Now, if we go back to decimal, it should come out to 0.3.

    So let’s try it: 0/2+1/4+0/8+0/16+1/32+1/64+0/128+0/256+1/512+0/1024 => 0.298828125

    WHAAAT?


  • There are several ways to achieve this. Also, “microfrontend” can mean many things. It’s usually referred to the architecture in which you can deploy an app shell, and other people or teams (or even companies) deploy their own, and you can include parts of their remote-deployed things into your live app. Look into Webpack 5 and Federated Modules for this. Look also into things like Single SPA. OR maybe Piral. There are other ways out there as well, but I haven’t tried them or they would not mix easily with Angular.

    Then perhaps you mean deploy-time or build-time integration. From simple monorepos like nx.dev or workspace-like things, to even straight-forward publishing every module on npm. You can pack Angular Standalone Components into a package without issues. But even if you have older Angular versions like you mention, you can export web-component-like components and push them into a (private) npm namespace, and assemble on build time. And the same on react.

    Then there are things like Astro, mentioned bellow, which kind of mix both of these ideas, and many more.

    Your question is quite broad. If you have specific requirements, e.g. “I have a repo with two components, an angular app, two react apps in these versions, and I want to achieve X”, you may get specific recommendations, so fire away, ask questions.








  • Yes, in fact! Two main reasons.

    • I wanted low-power, this is mostly gonna sit in the closet and serve files around. Even ARM CPUs like the RasPi can do that. But I didn’t want it to be too weak, in case I wanted a simple service or two, this still has extra oomph. This isn’t too powerful, but it is a 64-bit x86 CPU.

    • I also wanted some ports. This has 4 SATA ports. It’s supposed to be a NAS. It has a Gbit ethernet - I don’t have a Gbit network at home so this is good enough for now, and I can expand it somewhat. It has USBs, expansion slots etc.

    • those two combined resulted in a few selections, AsRock’s mini-ITX boards with integrated CPUs are quite good choices in this space.

    • I wanted low power consumption. I could have gone with a slightly stronger ‎J5040-ITX perhaps, but it’s also using just slightly more power.

    • it’s also cheaper, the mobo with the CPU cost me 120€. The j5040 I mentioned would be a bit more - not a lot but still noticable.

    • I wanted silent, and this board and CPU is passively cooled. If I had money, I would get SSDs for storage as well (less power, less noise) but it’s a LOT more expensive.

    I know there are other CPUs in this space but in the end you have to pick one so I did.