'**SUMMARY**
Returns a numpy array of the area of each feature in pixels.
**RETURNS**
A numpy array of all the positions in the featureset.
**EXAMPLE**
>>> img = Image("lenna")
>>> feats = img.findBlobs()
>>> xs = feats.area()
>>> print xs'

def area(self):

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