Write the classifier
Show on a big screenYou have written the nearest-example rule before. Now it works on a whole register, not just a few examples. A register is the list of judged kites. A walk goes through the list once, one example at a time. Met first means reached first when walking the list. One square away means one step on the board. Its squared distance is 1.
- A new kite at 8 span, 5 tail. Two examples sit one square away.
- T1, met first: squared distance 1. Best so far.
- T2, met next: squared distance 1 too. It is not strictly nearer. T1 stays best.
- The winner is T1. Its word, dancer, is the answer.
The rule
Measure every example and carry the nearest one so far. A new example wins only when it is strictly nearer. Ties keep the example met first.
let best = 0;let least = distanceSquared(newKite, examples[0]);if (d < least) { least = d; best = i; }
The name best holds the position of the nearest example so far. The name least holds its squared distance. The name d holds the squared distance of the example being checked. The name i holds that example's position. The walk starts at position 1. Position 0 is the first best.
Use <, not <=. That single sign is the whole tie rule. A later example replaces the best only when strictly nearer. Equal is not enough.
Write classify with a best-so-far walk. Return the nearest example's word.
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The five printed words should match the board you have already seen.
Try the lab to finish this lesson.