is-monotonic
checks that a given sequence is strictly increasing or decreasing
Example
const { isMonotonicIncreasing, isMonotonicDecreasing } = require('is-monotonic')
isMonotonicIncreasing([1, 2, 3, 4]) // true
isMonotonicIncreasing([1, 3, 2, 4]) // false
isMonotonicDecreasing([4, 3, 2, 1]) // true
isMonotonicDecreasing([4, 2, 3, 1]) // false