Python: 语法(持续更新)

版权声明：转载请注明出处！ https://blog.csdn.net/oliverchu/article/details/79573385

python2.7中,for循环语句的强大可以通过下列案例看出,你可能很少见到这样的使用方式:

'''
Algorithm for Python

'''
import random
import datetime

ranArray = []
ranArray = [x for x in range(100000)]


tStart = datetime.datetime.now()
tEnd = datetime.datetime.now()

def swapsort():
    random.shuffle(ranArray)
    arr = ranArray
    length = len(arr)
    start()
    for i in range(length):
        for j in range(i+1,length):
            if arr[i] > arr[j]:
                tem = arr[i]
                arr[i] = arr[j]
                arr[j] = tem
    print "Swap sort end."
    end()

def mutrixmult():
    a = [[1,2],[2,3]]
    b = [[7,22],[22,33]]
    c = [[0 for x in range(a)] for x in range(b)]
    for i in range(len(a)-1):
        for j in range(len(a[0]-1)):
            for m in range(b[0]-1):
                c[i][j] = a[i][j] * b[i][m] +a[i][j+1] * b[i][m+1]                 


def start():
    tStart = datetime.datetime.now()
def end():
    tEnd = datetime.datetime.now()
    print "Cost",tEnd - tStart

if __name__ == "__main__":
    #swapsort()
    mutrixmult()