Python is built with a playful function-zip, and the ingenious implementation randomly generates a finite number of strings by probability.

Python has a more interesting built-in function-----zip, you can put the two sets of the incoming list to a combination of deformation, and then output the sub-element is a list of tuple, but the way of deformation is more abstract.

As an example:

a=[1,2,3,4,5,6]b=['a','B','c ','d']v1=zip (A, B)

The results of the V1 are:

' a ' ' b ' ' C ' ' D ')]

The more intuitive understanding is that A and B are two zippers on the button, the resulting list of sub-tuple, each group of tuple is a pair of buttons buttoned up, and from the first element of each group of list "pull zipper", that a zipper is from the 1~6,b zipper is from the a~d, pull to the end, Obviously pull to D on the button, so the result is obvious: 1-a,2-b,3-c,4-d. 5,6 staggered.

If this is to be given a matrix, such as 3x3, and output in the following way:

a1=[1,2,3]; a2=[4,5,6]; a3=[7,8,9]

A1,a2,a3 represent each row of the matrix, and now make the following changes:

a1=[1,2,3]a2=[4,5,6]a3=[7,8,9]zip (A1,A2,A3)

The output is:

[(1, 4, 7), (2, 5, 8), (3, 6, 9)]

Three zippers can also be pulled up ~

a=-------Zip--------b= Here you can see that it's a transpose of the original matrix.

This time let b1,b2,b3 distribution reverse output, that is, output B1[::-1],B2[::-2],B3[::-3], obviously, the result is a clockwise rotation of 90° results

Similarly, if a nested list is passed in, the result can be output by means of a *, for example:

Zip (*[(1, 4, 7), (2, 5, 8), (3, 6, 9)]) Zip (*[[1, 4, 7], [2, 5, 8], [3, 6, 9]])

The output results are:

[(1, 2, 3), (4, 5, 6), (7, 8, 9)]

This very abstract function also has a magical magic----randomly generate a set of strings by probability

For example, for example, take 20 random strings, the candidate string includes a,b,c3, and the probability of each occurrence is called 0.1,0.3,0.6

def Random_pick (seq,probabilities):     = Random.uniform (0, 1)# First randomly generates a random number between 0 and 1    cumulative_probability = 0.0 for    in  zip (seq, probabilities): #seq代表待输入的字符串, prob represents the probability        of each corresponding string + = item_probability# Only jumps out when the cumulative probability is greater than the random number generated just now, and outputs the corresponding string         if x < cumulative_probability:              Break        return Item

For example:

First time x=0.09, the first cumulative probability is 0.1, satisfies the condition, jumps out and outputs the p=0.1 character

The second x=0.2, the first cumulative probability 0.1, does not meet and then accumulates to 0.4, jumps out the output p=0.3 the character

The third time x=0.3, the first cumulative probability 0.1, does not meet and then accumulates to 0.4, jumps out the output p=0.3 the character

The fourth time x=0.4, the first cumulative probability 0.1, does not meet and then accumulates to 0.4, still does not satisfy to accumulate to 1, jumps out the output p=0.6 character

Then x=0.5,0.6 .... 0.9, all output p=0.6 characters

It is obvious that such an output satisfies this probabilistic relationship and thus achieves the effect of outputting random strings by probability.

 for  in range:    print random_pick ("ABC", [0.1,0.3,0.6])

The output is:

Python is built with a playful function-zip, and the ingenious implementation randomly generates a finite number of strings by probability.