python_01

# #两个数字之和
number1 = 2.5
number2 = 3.6
sum = number1 + number2
print (f"{number1} + {number2} == {sum}")
# #数字的阶乘
def get_jiecheng(number):
    result = 1
    while number > 0:
        result *= number
        number -=1
    return result
print("jiecheng 6 = ",get_jiecheng(6))
print("jiecheng 5 = ",get_jiecheng(5))
print("jiecheng 80 = ",get_jiecheng(80))
#求园的面积
import math
def computer_area_of_circel(r):
    return round(math.pi * r * r,2)

print("area of 5 is: ",computer_area_of_circel(5))
print("area of 2.5 is: ",computer_area_of_circel(2.5))
print("area of 5.6 is: ",computer_area_of_circel(5.6))
#区间内所有素数     一个数字只能被自己和1整除

def is_prime(number):
    if number in(1,2):
        return True
    for idx in range (2,number):
        if number % idx  == 0:
            return False
    return True

def print_primes(begin,end):
    for number in range(begin,end+1):
        if is_prime(number):
            print(f"{number} is a prime")
begin = 1
end = 8
print_primes(begin,end)
#求前n个数字的平方和
def sum_of_square(n):
    result = 0
    for number in range(1,n+1):
        result += number * number
    return result
print("number 3 square is:",sum_of_square(3))
print("number 5 square is:",sum_of_square(5))
print("number 8 square is:",sum_of_square(8))
#列表数字之和
def sum_of_list(parm_list):
    total = 0
    for item in parm_list:
        total += item
    return total
list1 = {1,2,5,8}
list2 = {15,85,95,865}
print(f"sum of {list1}:",sum_of_list(list1) )
print(f"sum of {list2}:",sum_of_list(list2) )

print(f"sum of {list1}:",sum(list1) )    #sum函数一步到位
print(f"sum of {list2}:",sum(list2) )

#计算数字范围内所有偶数
def get_even_number(begin,end):
    result = []
    for item in range(begin,end+1):
        if item % 2 ==0:
            result.append(item)
    return result
begin = 12
end = 17
print(f"begin={begin},end={end},even number",get_even_number(begin,end))
date = [item for item in range(begin,end+1) if item % 2 == 0]    #date函数一步到位
print(f"begin={begin},end={end},even number",date)
#移除列表中的多个元素
def remove_elements_from_list(list1,list2):
    for item in list2:
        list1.remove(item)
    return list1
list1 = [45,5,6,85,99]
list2 = [5,6]
print(f"from {list1} remove {list2 },result",remove_elements_from_list(list1,list2))
list1 = [45,5,6,85,99]
list2 = [5,6]
date = [item for item in list1 if item not in list2]
print(f"from {list1} remove {list2 },result",date)
#对列表元素去重
def get_unique_list(list1):
    result = []
    for item in list1:
        if item not in result:
            result.append(item)
    return result
list1 = [1,2,3,3,5]
print(f"source list {list1},unique list:",get_unique_list(list1))
print(f"source list {list1},unique list:",list(set(list1)))  #set 函数是没有重复元素的  想转换set为list 则需要在 set 前加上一个列表list。
#怎么对简单列表元素进行排序
list1 = [1,2,56,4,5,6,878]
#list2 = [kk,jj,h,u,t]
list1.sort(reverse = True )           #list1.sort 函数一样包括判断条件reverse = Ture 来进行升序或者降序的判断。
list3 = sorted(list1,reverse = True )    # sorted 函数中列表后可以加判断reverse = True 或者是False 来进行升序或者降序排列。
print(f"list1 is {list1}")
print(f"list1 is {list3}")
#实现学生成绩排序：lambda 函数做字典排序  用到一个 x：X 第一个x代表字典里面的一个列表，后面一个x代表当前列表中的一个可以用作比较的参数值作为比较参数，在元组列表中，可以把x : x 比作x0：xn这样的顺序去对列表中的元素进行排序。
#sort_student_list
student = [
    {"sno":101,"name":"小张","sgrade":88},
    {"sno":102,"name":"小王","sgrade":95},
    {"sno":103,"name":"小李","sgrade":66},
    {"sno":104,"name":"小赵","sgrade":55},
]
student_sort = sorted(student,
                      key=lambda x : x["sgrade"],
                      reverse=True)
print(f"source {student},"
      f"sort result:{student_sort}")
#读取成绩文件排序数据：
def read_file():
    result = []
    with open("./student_grade_input.txt",encoding="utf-8") as fin:
        for line in fin:
            line = line[:-1]
            result.append(line.split("，"))
    return result
def sort_grades(dates):
    return sorted(datas,
                  key=lambda x: int(x[2]),
                  reverse =True )
def write_file(datas):
    with open("./student_grade_output.txt","w",encoding="utf-8") as fout:
        for data in datas:
            fout.write("，".join(data) + "\n")


# 读取student_grade_input.txt文本文件内容
datas = read_file()
print("read_file datas:",datas)
# 对读取出来的内容可以进行排序
datas = sort_grades(datas)
print("sort_grades datas:",datas)
# #对排序整理过的文件我们进行输出到新的文本文档保存
write_file(datas)