it("should average the fixed values", () => {
      const N = 100
      const vals = repeat(5, N)
      const rets = transform.v_compute(vals)

      const thesum = sum(rets)
      const thediff = thesum/N - 5
      // We can set this deterministically because we've stubbed random
      expect(thediff).to.equal(0)
    })

 private _get_snap_coord(array: Arrayable<number>): number {
   return sum(array) / array.length
 }