python如何计算平均分_如何计算python中元组列表的平均值？

干得好：

the_list = [('msft', '$31', 5), ('msft','$32', 10), ('aapl', '$100', 1)]

clean_list = map (lambda x: (x[0],float (x[1][1:]), int(x[2])), the_list)

out = {}

for name, price, shares in clean_list:

if not name in out:

out[name] = [price, shares]

else:

out[name][0] += price * shares

out[name][1] += shares

# put the output in the requested format

# not forgetting to calculate avg price paid

# out contains total # shares and total price paid

nice_out = [ (name, "$%0.2f" % (out[name][0] / out[name][1]), out[name][1])

for name in out.keys()]

print nice_out

>>> [('aapl', '$100.00', 1), ('msft', '$23.40', 15)]