#1 import numpy as np

[Eric Schug]

Importing everything is a source of possible errors (e.g. pylab
overwrites numpy names)

from numpy import *
import scipy
# if available import pylab (from matlibplot)
try:
from pylab import *
except ImportError:
pass

I would prefer the current standard
import numpy as np
import matplotlib.pylab as plt

and keep the name space as part of the name, e.g. np.dot, np.exp, ...