import numpy as np

class Store(object):
    pass

def function0():
    y = 0
#    x = np.random.randn(20,20)
#    y = np.linalg.inv(x)
#    y = np.corrcoef(x)
    return y

def function1():
    result = Store()
    result.a = np.arange(5)
    result.b = function0()
    return result

def function2():
    return np.arange(5), function0()
    
def function3():
    result = function1()
    return result.a, result.b

def function4(full_output=True):
    if full_output:
        result = Store()
        result.a = np.arange(5)
        result.b = function0()
        return result
    else:
        return np.arange(5), function0()

if __name__=='__main__':
    from timeit import Timer
    n = 10000
    t = Timer("r = function1()", "from __main__ import np,Store,function1")
    t1 = t.timeit(n)
    print 'function1', t1
    t = Timer("r = function2()", "from __main__ import np,Store,function2")
    t2 = t.timeit(n)
    print 'function2', t2
    t = Timer("r = function3()", "from __main__ import np,Store,function3")
    t3 = t.timeit(n)
    print 'function3', t3, t3/t2
    t = Timer("r = function1()", "from __main__ import np,Store,function1")
    t1 = t.timeit(n)  #repeated
    print 'function1', t1, t1/t2
    t = Timer("r = function4()", "from __main__ import np,Store,function4")
    t4a = t.timeit(n)
    print 'function4a', t4a, t4a/t2
    t = Timer("r = function4(full_output=0)", 
              "from __main__ import np,Store,function4")
    t4b = t.timeit(n)
    print 'function4b', t4b, t4b/t2