Pythonに関するメモ

コメントアウト

01_Commnet_Out_Test.py（サンプル）

#! /usr/bin/python
# coding: UTF-8

def Comment_Out_Test():
    #print("コメントアウト")
    print("1")

    '''
    print("コメントアウト")
    '''
    print("2")

#main function
if __name__ == "__main__":
    Comment_Out_Test()

List操作

02_List_Test.py（サンプル）

#! /usr/bin/python
# coding: UTF-8

def List_Test():
    a = list(range(10))

    print("a = " + str(a))
    
    b = list(range(3,4))
    print("b = " + str(b))
    
    c = a+b
    print("c = " + str(c))
    
    e = c[1:5]
    print("e = " + str(e))
    
    f = e[:-1]
    print("f = " + str(f))
    
    g = f[::-1]
    print("g = " + str(g))
    
    h = g[-1]
    print("h = " + str(h))

    
#main function
if __name__ == "__main__":
    List_Test()

（実行結果）
a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
b = [3]
c = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 3]
e = [1, 2, 3, 4]
f = [1, 2, 3]
g = [3, 2, 1]
h = 1

例外処理

04_try_exception.py（サンプル）

#! /usr/bin/python
# coding: UTF-8

import sys

def Try_Except():
    try:#エラーがおきるかもしれない処理
        file = open ('log.txt','a') 
        print("File opened")
        file.write("OK\n")
        print("OK")
    except Exception as e:     #エラーが起きた時
        print("Error:"+str(e))
    finally:    #エラーの有無に関わらず必ず実行
        file.close()
        print("File closed")
        
#main function
if __name__ == "__main__":
    Try_Except()