value change error

[tkzcfc]

local tween = require("tween")

local obj = {x = 0}
local tw = tween.new(1.5, obj, {x = 1}, "inExpo")
tw:update(1 / 40)

print("x", obj.x)

tw:update(1 / 40)
print("x", obj.x)

print:

x 9.6154344052123e-005
x 0.00023039165028796