In [40]:

    

%pylab inline


    

    




Populating the interactive namespace from numpy and matplotlib

In [41]:

    

x = arange(0,30)


    

In [42]:

    

x = x.reshape((30,1))


    

In [43]:

    

error = np.random.normal(0,15,(30,1))


    

In [44]:

    

y = 5*x+2+error


    

In [45]:

    

scatter(x,y)


    

    
Out[45]:





<matplotlib.collections.PathCollection at 0x93d8518>






    

In [46]:

    

A = hstack([x, ones_like(x)])


    

In [47]:

    

v = linalg.lstsq(A, y)[0]
v


    

    
Out[47]:





array([[ 4.90957816],
       [-1.08990893]])

In [48]:

    

plot(x,dot(A, v),"r")
scatter(x,y)


    

    
Out[48]:





<matplotlib.collections.PathCollection at 0x955dd68>






    

In [49]:

    

y =3*x**2+15*x+2+error


    

In [50]:

    

scatter(x,y)


    

    
Out[50]:





<matplotlib.collections.PathCollection at 0x97a3da0>






    

In [51]:

    

A = hstack([x**2,x, ones_like(x)])


    

In [52]:

    

v = linalg.lstsq(A, y)[0]
v


    

    
Out[52]:





array([[  2.91833232],
       [ 17.27794096],
       [-12.14226866]])

In [53]:

    

plot(x,dot(A, v),"r")
scatter(x,y)


    

    
Out[53]:





<matplotlib.collections.PathCollection at 0x98d70f0>






    

In [ ]:

    




    

In [ ]:

    




    

In [ ]:

    




    

In [ ]: