연산자 학습

  1. 숫자 연산
In [11]:
# 연산자
a= 11; b= 4
print(a+b)
print(a-b)
print(a*b)
print(a/b)
print(a//b) #정수값만 출력한다.
print(a % b)

15
7
44
2.75
2
3
In [17]:
print(a**b)#a*a*a*a
print(a*a*a*a)

#경고 예외발생!
c=0
print(a/c)

14641
14641

---------------------------------------------------------------------------
ZeroDivisionError                         Traceback (most recent call last)
c:\Repository\StudyPython_2022\day1\연산자.ipynb Cell 3' in <cell line: 6>()
      <a href='vscode-notebook-cell:/c%3A/Repository/StudyPython_2022/day1/%EC%97%B0%EC%82%B0%EC%9E%90.ipynb#ch0000003?line=3'>4</a> #경고 예외발생!
      <a href='vscode-notebook-cell:/c%3A/Repository/StudyPython_2022/day1/%EC%97%B0%EC%82%B0%EC%9E%90.ipynb#ch0000003?line=4'>5</a> c=0
----> <a href='vscode-notebook-cell:/c%3A/Repository/StudyPython_2022/day1/%EC%97%B0%EC%82%B0%EC%9E%90.ipynb#ch0000003?line=5'>6</a> print(a/c)

ZeroDivisionError: division by zero
  1. 문자열 연산
In [27]:
#문자열 연산
first = 'Hello,'
second = 'world'
print (first+" "+second)
#print (second + 5) # 안 됨
print(second * 5)
#print(first-second) # 안 됨
#print(first/second) # 안 됨
#print(first/2) # 안 됨

Hello, world
worldworldworldworldworld
In [41]:
# 문자열
print(first[0])
print(first[1])
print(first[2])
print(first[3])
print(first[4])
print(first[5])
print(first[-1])
print(len(first))
print(first[-6])

H
e
l
l
o
,
,
6
H
In [77]:
#현재 시간
current = '2022-05-23 17:33:45'
print(current)
curr_date = current.split(' ')
print(curr_date)
print(curr_date[0])
print(curr_date[1])
print(type(curr_date))
print(curr_date[0][:4]+'\n')

year=current[0:4] # year=current[:4]
month=current[5:7]
day=current[8:10]
hour=current[11:13]
min=current[14:16]
sec=current[17:19]#  sec=current[17:]
print(year)
print(month)
print(day)
print(hour)
print(min)
print(sec+'\n')
print(current[-2:])
print(current[-5:-3])

2022-05-23 17:33:45
['2022-05-23', '17:33:45']
2022-05-23
17:33:45
<class 'list'>
2022

2022
05
23
17
33
45

45
33