'**SUMMARY**
Return a numpy array of the angles (theta) of each feature.
Note that theta is given in degrees, with 0 being horizontal.
**RETURNS**
An array of angle values corresponding to the features.
**EXAMPLE**
>>> img = Image("lenna")
>>> l = img.findLines()
>>> angs = l.angle()
>>> print angs'

def angle(self):

    return np.array([f.angle() for f in self])
