JS math thing

math_thing.js

var accelX = Accel.getX //Assuming Accel.getX can read from Pebble or whatever
var accelY = Accel.getY
var accelZ = Accel.getZ

var threshold = 14.5 //total accel bigger than this means seizure

//METHOD 1: Checking xyz individually
if (accelX > threshold || accelY > threshold || accelZ > threshold ) {
  console.log('seizure')
}
//The above will fail in some cases!
//Imagine x = 14, y = 14, z = 0.
// x,y,z are individually less than threshold (14.5), but the combined 
// accel is actually sqrt(x^2 + y^2 + z^2) = 19.8


//BETTER METHOD: Use vector magnitude

totalAccel = Math.sqrt(Math.pow(accelX, 2) + Math.pow(accelY, 2) + Math.pow(accelZ, 2))

if (totalAccel > threshold) {
  console.log('seizure!')
}