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    1. Any motorcyclists?

      I'm about to do my full motorbike licence here in the UK (direct access course) and currently looking at my first big bike, thinking about a 600cc Triumph at the moment. Wondered if there are any...

      I'm about to do my full motorbike licence here in the UK (direct access course) and currently looking at my first big bike, thinking about a 600cc Triumph at the moment. Wondered if there are any other riders here on tildes, what do you ride, what's your history with bikes etc.?

      16 votes
    2. Programming Challenge: Convert between units

      Hi everyone! It's been a long time since last programming challenge list, and here's a nice one I've encountered. If you search for something like 7km to AU, you'll get your answer. But how is it...

      Hi everyone! It's been a long time since last programming challenge list, and here's a nice one I've encountered.

      If you search for something like 7km to AU, you'll get your answer. But how is it done? I don't think they hardcoded all 23 units of distance and every conversion factor between them.

      If you were programming a conversion system - how would you do it?

      First of all, you have input in format that you can specify, for example something like this:

      meter kilometer 1000
      mile kilometer 1.609344
      second minute 60
      ...
      

      Then you should be able answer queries. For example 7 mile meter should convert 7 miles to meters, which is 11265.41.

      Can you design an algorithm that will convert any unit into any other unit?

      Edit: Some conversion rates I extracted from wikipedia:

      ångström
      0.1nm
      astronomical unit
      149597870700m
      attometre
      0.000000000000000001m
      barleycorn
      8.4m
      bohr
      0.00846
      cable length (imperial)
      185.3184m
      cable length
      185.2m
      cable length (US)
      219.456m
      chain (Gunters)
      20.11684m
      cubit
      0.5m
      ell
      1.143m
      fathom
      1.8288m
      femtometre
      0.00000000000001m
      fermi
      0.00000000000001m
      finger
      0.022225m
      finger (cloth)
      0.1143m
      foot (Benoit)
      0.304799735m
      foot (Cape) (H)
      0.314858m
      foot (Clarke's) (H)
      0.3047972654m
      foot (Indian) (H)
      0.304799514m
      foot,metric
      0.31622776602m
      foot,metric (long)
      0.3m
      foot,metric (short)
      0.30m
      foot (International)
      0.3048m
      foot (Sear's) (H)
      0.30479947m
      foot (US Survey)
      0.304800610
      french
      0.0003m
      furlong
      201.168m
      hand
      0.1016m
      inch
      0.0254m
      league
      4828m
      light-day
      25902068371200m
      light-hour
      107925284880m
      light-minute
      17987547480
      light-second
      299792458m
      light-year
      31557600light-second
      line
      0.002116m
      link (Gunter's)
      0.2011684m
      link (Ramsden's; Engineer's)
      0.3048m
      metre
      1m
      m
      1metre
      km
      1000m
      mickey
      0.000127
      micrometre
      0.000001
      mil; thou
      0.0000254
      mil
      10km
      mile (geographical)
      6082foot (International)
      quarter
      0.2286m
      rod
      5.0292m
      rope
      6.096m
      shaku
      0.303 0303m
      span (H)
      0.2286m
      stick (H)
      0.0508m
      toise
      1.949 0363m
      twip
      1.76310
      yard
      0.9144m
      
      17 votes
    3. Dan Tepfer (Human - Computer Duet) - NPR Music Tiny Desk Concert

      Video Link I decided to post this as a text topic since IMO the video description is really important to understanding this performance: Aug. 29, 2019 | Colin Marshall -- Dan Tepfer has...

      Video Link

      I decided to post this as a text topic since IMO the video description is really important to understanding this performance:

      Aug. 29, 2019 | Colin Marshall -- Dan Tepfer has transformed the acoustic piano entirely with his new project, Natural Machines. Watch the keys and you'll see this Disklavier — a player piano — plucking notes on its own. But it's not a prerecorded script.

      Here's how it works: Tepfer plays a note, and a computer program he authored reads those notes and tells the piano what to play in response. Tepfer can load different algorithms into the program that determine the pattern of playback, like one that returns the same note, only an octave higher. Another will play the inverted note based on the center of the piano keys. These rules create interesting restrictions that Tepfer says make room for thoughtful improvisation. In his words, he's not writing these songs, so much as writing the way they work. To better communicate what's happening between him and the piano, Tepfer converted these audio-impulse data into visualizations on the screen behind him, displaying in real time the notes he plays followed by the piano's feedback. We dive even deeper into this project in a recent Jazz Night in America video piece.

      Perhaps the trickiest part here, unlike a human-to-human duo, is that the computer plays along with 100 percent accuracy based solely on Tepfer's moves. He compares it to dancing with a robot that never misses a beat. Tepfer has to play in kind to keep the train on the tracks, but if he falls out of step, so does the computer. On the other hand, Tepfer has unlocked a new frontier of music available to acoustic piano players: He's essentially given himself more limbs to play the piano at once, and at times we see more than 10 keys pressed at a time or a sequence of notes played at seemingly superhuman speeds. It's a central idea to what innovative technology enables for us — that which is impossible for us to achieve on our own.

      edit: Nice related video from Jazz Night in America with Dan explaining some of how it works:
      https://www.youtube.com/watch?v=0L6tzG3FkcU

      7 votes