python練習問題練習(一)

3113 ワード

参考書:pythonプログラミング
chapter 1
5.

print("This program illustrates a chaotic function")
x = eval(input("Enter a number between 0 and 1:"))
n = eval(input("How many times shoule I print?"))
for i in range(n):
    x = 3.9 * x * (1 - x)
    print(x)

chapter2

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4.


def convert():
    celsius = eval(input("What's the Celsius temperature?"))
    fahrenheit = 9/5 * celsius + 32
    print("The temperature is ", fahrenheit, "degrees Fahrenheit.")

for i in range(5):
    convert()

5.


def main():
    celsius = 0
    for i in range(11):   
        fahrenheit = 9/5 * celsius + 32
        print("Celsius", celsius, "equals to Fahrenheit", fahrenheit, ".")
        celsius += 10
main()

7.


def main():
    print("This program calculates the future value.")

    year = eval(input("How may years do  you want?"))
    principal = eval(input("How much the principal each year?"))
    apr = eval(input("Enter the annual interest rate:"))

    value = principal
    for i in range(year):
        value = (1 + apr) * value
        value += principal
    print("The value in", year, "years is: ", value)

main()

12.


def main():
    print("This program calculates the expression's result.")

    for i in range(100):
        expr = eval(input("Enter an expression:"))
        print(expr)

main()

chapter3

10.


import math

def main():
    print("This program calculates the length of ladder.")

    angle = eval(input("Enter the angle:")) # degree
    radians = angle * math.pi / 180 # radians
    height = 10
    length = height / math.sin(radians)
    print("The length of ladder is", length, ".")

main()

11.


def main():
    print("This program calculates the sum of n natural numbers.")

    num = eval(input("Please enter the number:"))
    s = 0
    for i in range(num + 1):
        s += i
    print("The sum is", s, ".")

main()

15.


import math
def main():
    num = eval(input("Please input the number:"))
    s = 0
    for n in range(num):
        s = s + (-1)**(n) * 4/(2 * n + 1)
    error = math.pi - s
    print("The sum is:", s, ".")
    print("The error is,", error, ".")

main()