Python でサクッとLeast Square fit

Pythonで最小二乗を使うときはサクッと以下のように行おう。

import numpy as np
from scipy.optimize import leastsq

def func(c, x):
    return c[0]*x**2 + c[1]*x + c[2] 

def errfunc(c, x, t):
    return t - func(c, x)

#observed data and initial guess
x = np.linspace(-5, 5, 100)
t = 4*x**2 + 1 
c0 = [0, 0, 0]

leastsq(errfunc, c0, args=(x, t))