• 1 Post
  • 17 Comments
Joined 2 years ago
cake
Cake day: July 4th, 2022

help-circle



  • A couple of ideas:

    Encoding holograms

    • Model the object in 3D space (using Blender maybe?)
    • Use the Angular Spectrum algorithm to model light propagation, its interaction with the object, and it hitting the recording medium.
    • Your final recorded hologram should have two maps (aka “images”) across (x, y): a map of the light’s amplitude and another of its phase offset. This is your recorded hologram.

    Decoding holograms:

    • Use the angular spectrum algorithm again except reverse the light’s propagation direction. The amplitude and phase maps from the encoding phase are the initial conditions you’ll use for the light.
    • The light’s amplitude and phase information you calculate at various planes above the recording plane are the 3D “reconstructed” image.

    Last thought

    Holography is often used to record information from the real world, and in that process it’s impossible to record the light’s phase during the encode step. Physicist’s call it “the phase problem” and there are all kinds of fancy tricks to try to get around it when decoding holograms in the computer. If you’re simulating everything from scratch then you have the luxury of recording the phase as well as the amplitude - and this should make decoding much easier as a result!










  • Personally, I’ve used many trackers over the years. I currently use Loop Habit tracker but only for recording the information day-to-day. I periodically export my data in .csv format and merge it with my “long term storage” in a big spreadsheet which contains >10 years of data. I like doing it this way because I like to do statistics on it, plot it, etc. and that’s very easy in .csv format on a computer (I’m a nerd).

    Because my “long term storage” is just a simple .csv I don’t need to worry about compatibility between apps. Also, if I lose my phone it’s not a big deal because I’d lose, at the most, a few months.


  • Here are a couple of ideas:

    • Loop Habit has the ability to save a full backup. Maybe try setting up your habits, add some fake data, and generate the backup. Open the backup file in a text editor and see whether you can infer the structure. If so, just reformat your old data to match that structure and then import that “hacked” backup file back into Loop.
    • Loop Habit says it can import backup files from Tickmate, Habitbull, and Rewire as well. Similar to the above idea, if you can reformat your saved data to match one of those formats you should be able to import it into Loop.

  • Thoreau describes the cabin as a single 10 x 15’ room with very few possessions, so there wouldn’t be much to clean. And he spent a significant amount of the book describing cleaning routines. So yeah, I expected no housekeeper for sure.

    What’s your source for the housekeeper claim? I tried some internet searching but couldn’t find anything mentioning a housekeeper.