Lattice Multiplication

[davidn]

Why on earth didn't anyone teach me about this when I was in school! I've been covering the whiteboard in these ever since I saw this going past on Facebook (I haven't yet found definitive proof that it's of Japanese origin).

After a couple of fascinated scribbles (please excuse the mouse handwriting), I realized that by counting the intersections, you're doing exactly the same thing as the normal long multiplication method of multiplying each position by each other position, just laying it out visually... but it's so satisfying to see it fall out of a tartan picnic rug like that. Besides, it's prettier than a column of numbers.

I will have to remember this for when I next have paper to hand but not a calculator, which in today's environment will be round about never.

Comments

[premchaia_pre4]

Unfortunately, your sudden motion of the creature sets off the Chirp Alarm. CHIRP!! CHIRP!! CHIRP!! After the third chirp, sixteen talons, a beak, teeth, two sharp-edged wings, and a tailspear all set to slicing up and skewering your backpack simultaneously in a whirling ball of doom. Within seconds, the backpack lies in ribbons on the floor along with its disgorged contents, and not long after that, so do you.

It's a sad thing that your adventure has ended here!!

[xaq.livejournal.com]

...You'd think I'd have seen that coming.


(Note to self: upgrade to orihalcon-plated backpack.)