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Show HN: Pi Explained Visually

by vicapow on 11/28/14, 1:52 PM with 7 comments

  • by netcan on 11/28/14, 5:36 PM

    I was recently thinking about defining things vs explaining them. When you're trying to understand something, I think it's easier to use a story like approach. "If you take the line making a circle (or circumference if you already know that one) and measure its length. Then you take the diameter…"

    Once you know something, it's easier to shift that knowledge into a definition. "the ratio of a circle's diameter to its circumference." It's more concise and is more usable to tell subsequent stories and make subsequent definitions.

    I think this might be a common mistake when explaining things. When we understand something, it's kind of stored as a stack of definitions. "Ratio between diameter and circumference" assumes the learner knows ratio, diameter and circumference. If they don't, the tendency is to build up their definitions. "Ratio is __. circumference is __. pi is__…" But definitions take a bit more effort to plug into your brain.

    I think there's a programming paradigm analogy though I'm not quite fluent enough in the concepts to be confident about it. To venture.. a declarative programming's "Case Where" expression is more difficult to grasp than procedural "if then" if you're not familiar with conditionals in general.

    I think this is why encyclopedias can be hard to understand. They kind of define things.

  • by 0942v8653 on 11/28/14, 4:17 PM

    The best way I've seen pi explained visually is pi-unrolled.gif: https://commons.m.wikimedia.org/wiki/File:Pi-unrolled-720.gi...

  • by rahimnathwani on 12/1/14, 4:22 AM

  • by axotty on 11/28/14, 5:24 PM

    This would be a great resource for an advanced second grader.

  • by NaNaN on 11/28/14, 4:41 PM

    There are just definitons. Not interesting at all.