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Joined 9 months ago
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Cake day: September 14th, 2024

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  • It wouldn’t be a 30% higher electrical bill overall. It would be 30% more for whatever power you’re using for this specific device, which, if it’s ordinarily 10W while in sleep and an average 100W while in use, and you use it 50 hours per week, or 215 hours per month, that’s a baseline power usage of 21500 watt hours in use and 5050 watt hours from idle/sleep/suspend. Or a total of 26550 watt hours, or 26.5 kWh. At 20 cents per kWh, you’re talking about $5.30 per month in electricity for the computer. A 30% increase would be an extra $1.60 per month.





  • I can’t answer for dual numbers, but I can answer for imaginary numbers in circuit design.

    Imaginary numbers are those that include an imaginary component, that squares into a negative number. Traditionally, i^2 = -1, but electrical engineers like to use j instead (I tends to be a variable used to describe electrical current).

    Complex numbers, that include a real component and an imaginary component, can be thought of as having an “angle,” based on how much of it is imaginary and how much of it is real, mapped onto a 2-dimensional representation of that number’s real and imaginary components. 5 + 5j is as real as it is imaginary, so it’s like having a 45° angle. The real number 5 is completely real, so it has a 0° angle.

    Meanwhile, in alternating current (AC) circuits, like what you get from your wall outlet, the voltage source is a wave that alternates between a maximum peak of positive voltage and a bottom trough of negative voltage, in a nice clean sinusoidal shape over time. If you hook up a normal resistor, the nice clean sinusoidal voltage also becomes a nice clean sinusoidal current with the exact same timing of when the max voltage matches up with the max current.

    But there’s also capacitors, which accumulate charge so that the flow of current on the other side depends on its own state of charge. And there are inductors, that affect current based on the amount of energy stored magnetically. These react to the existing current and voltage in the system and manipulate the time relationship between what moment in time a peak current will happen and when the peak voltage was.

    And through some interesting overlap in how adding and subtracting and delaying sinusoidal waves works, the circuit characteristics line up perfectly with that complex angle I was talking about, with the imaginary numbers. So any circuit, or any part of a circuit, can be represented with an “impedance” that has both an imaginary and real component, with a corresponding phase angle. And that complex number can be used to calculate information about the time delay in the wave of current versus the wave of voltage.

    So using complex phase angles makes certain AC calculations much, much easier, to represent the output of real current from real voltage, where the imaginary numbers are an important part of the calculation but not in the actual real world observation itself.

    So even though we start with real numbers and end with real numbers, having imaginary numbers in the toolbox make the middle part feasible.








  • Spit out a random e-mail address and record which e-mail address was given to each IP.

    The author mentions it’s a violation of GDPR to record visitors’ IP addresses. I’m not sure that’s correct, but even so, it could be possible to make a custom encoding of literally every ipv4 address through some kind of lookup table with 256 entries, and just string together 4 of those random words to represent the entire 32-bit address space, such that “correct horse battery staple” corresponds to 192.168.1.100 or whatever.


  • Base64 encoding of a text representation of an IP address and date seems inefficient.

    There are 4 octets in a ipv4 address, where each octet is one of 2^8 possible integers. The entire 32-bit ipv4 address space should therefore be possible to encode in 6 characters in base64.

    Similarly, a timestamp with a precision/resolution in seconds can generally be represented by a 32-bit integer, at least up through 2038. So that can be represented by another 6 characters.

    Or, if you know you’re always going to be encoding these two numbers together, you can put together a 64-bit number and encode that in base64, in just 11 characters. Maybe even use some kind of custom timestamp format that uses fewer bits and counts from a more recent epoch, as an unsigned integer (since you’re not going to have site visitors from the past), and get that down to even fewer characters.

    That seems to run less risk of the email address getting cut off at some arbitrary length as it gets passed around.


  • The use of a “+” convention is just a convention popularized by Gmail and the other major providers. If you have your own domain, you should be able to do this with any arbitrary text schema, and encode some information in the address itself, especially if you don’t care about sending email from those aliases: set up your email service to have a catchall inbox that can further be filtered/forwarded based on other rules.

    It can be cumbersome but I could see it working at getting the information you’re looking for.






  • I still have a few reddit alts that I lurk with, at least until we get enough activity on Lemmy on those topics:

    • Sports discussion, including specific leagues and teams
    • Discussion about my specific local city (and maybe the other cities I frequently visit)
    • Things relevant to my career/industry in law
    • Economics and financial news
    • Food and cooking
    • Television shows and movies, including specific shows or narrow discussions
    • Super specific hobbies and interests, not just the stuff I’m personally into, but also knowing that there’s a community around some other hobby so that there is lots of archived discussion where I can just click around and learn something new. For example, the most recent plane crashes in DC and Toronto, I went to the aviation community on Reddit to see what experienced professionals were saying about those things as the news broke.

    Lemmy’s good on all the tech and science stuff I like, and most of the memes/humor that I’m looking for. It’s coming along on some mainstream interests, including the ones I’ve listed above, but still has a ways to go before the organic discussions reach the level of detail and expertise that reddit has. But it’s on the right track, and I’m optimistic about those things filling in over time.