[Raspberry Pi] 3. 파이썬 기초 : 내장 함수, 형변환, len, 조건문, 반복문, range(), time.sleep(), 함수 작성 / Hello World, LED 켜기, 깜빡이기

https://github.com/upcake/Class_Examples

교육 중에 작성한 예제들은 깃허브에 올려두고 있습니다. 

gif 파일은 클릭해서 보는 것이 정확합니다.

---

 - 파이썬 기초 : 내장 함수(upper, lower, count, swapcase, replace, split), 형변환, len -

#builtin function
#upper, lower, count, swapcase
a = "Good morning, Man"
print(a.upper())
print(a.lower())
print(a.count('o'))
print(a.swapcase())

#replace
a = "Life is too short"
print(a.replace("Life", "Your height"))

#split
a = "I regret what I did to you"
print(a.split())

d = "home, mother, sweet"
print(d.split(','))
print(d.split(","))

#casting
n = int('123') #string > number
f = float("365.7") #string > float
s = str(123) #number > string
ss = str(456) + "789"
print(n)
print(f)
print(s)
print(ss)

#len
print(len("hi"))

▲내장 함수, 형변환, len

>>> %Run 200708_1.py
GOOD MORNING, MAN
good morning, man
3
gOOD MORNING, mAN
Your height is too short
['I', 'regret', 'what', 'I', 'did', 'to', 'you']
['home', ' mother', ' sweet']
['home', ' mother', ' sweet']
123
365.7
123
456789
2
>>> 

▲실행 결과

 

 - 파이썬 기초 : 조건문(if, while), 반복문(for), range(), time.sleep() -

#if
name = 'jane'
if name == 'jane':
    print("name is jane")
else :
    print("name is not jane")

age = 35
if age > 30 :
    print('more than 30')
else :
    print('less than 30')
    
a = 5
if a == 5:
    print ('True')
else:
    print ('False')

if a > 3 and a < 10:
    print ('True')
else:
    print ('False')

#elif
if a == 4:
    print ('number is 4')
elif a < 10:
    print ('number less than 10')
else:
    print ('number is something')

#while
a = 0
while a < 10:
    a = a + 1
    print (a)
    
#for
odd_number = [1, 3, 5, 7, 9, 11, 13]
for num in odd_number:
    print(num)

number = [1, 2, 3, 4, 5, 6, 7]
for num in number:
    if num % 2 == 0:
        print(num)

#range()
range(10) #0 ~ 9
range(5, 10) #5 ~ 9
range(10, 20, 2) #10, 12, 14, 16, 18

for i in range(10):
    print(i)
    
#gugudan
for x in range(2, 10):
    print("-------[" + str(x) + "dan]--------")
    for y in range(1, 10):
        print(x, " X ", y, " = ", x*y)
    print("---------------------")

#time
#sleep(second)
import time
for i in range(10):
    print(i)
    time.sleep(0.1)

▲조건문, 반복문, range(), time.sleep()

 

>>> %Run 200708_2.py
name is jane
more than 30
True
True
number less than 10
1
2
3
4
5
6
7
8
9
10
1
3
5
7
9
11
13
2
4
6
0
1
2
3
4
5
6
7
8
9
-------[2dan]--------
2  X  1  =  2
2  X  2  =  4
2  X  3  =  6
2  X  4  =  8
2  X  5  =  10
2  X  6  =  12
2  X  7  =  14
2  X  8  =  16
2  X  9  =  18
---------------------
-------[3dan]--------
3  X  1  =  3
3  X  2  =  6
3  X  3  =  9
3  X  4  =  12
3  X  5  =  15
3  X  6  =  18
3  X  7  =  21
3  X  8  =  24
3  X  9  =  27
---------------------
-------[4dan]--------
4  X  1  =  4
4  X  2  =  8
4  X  3  =  12
4  X  4  =  16
4  X  5  =  20
4  X  6  =  24
4  X  7  =  28
4  X  8  =  32
4  X  9  =  36
---------------------
-------[5dan]--------
5  X  1  =  5
5  X  2  =  10
5  X  3  =  15
5  X  4  =  20
5  X  5  =  25
5  X  6  =  30
5  X  7  =  35
5  X  8  =  40
5  X  9  =  45
---------------------
-------[6dan]--------
6  X  1  =  6
6  X  2  =  12
6  X  3  =  18
6  X  4  =  24
6  X  5  =  30
6  X  6  =  36
6  X  7  =  42
6  X  8  =  48
6  X  9  =  54
---------------------
-------[7dan]--------
7  X  1  =  7
7  X  2  =  14
7  X  3  =  21
7  X  4  =  28
7  X  5  =  35
7  X  6  =  42
7  X  7  =  49
7  X  8  =  56
7  X  9  =  63
---------------------
-------[8dan]--------
8  X  1  =  8
8  X  2  =  16
8  X  3  =  24
8  X  4  =  32
8  X  5  =  40
8  X  6  =  48
8  X  7  =  56
8  X  8  =  64
8  X  9  =  72
---------------------
-------[9dan]--------
9  X  1  =  9
9  X  2  =  18
9  X  3  =  27
9  X  4  =  36
9  X  5  =  45
9  X  6  =  54
9  X  7  =  63
9  X  8  =  72
9  X  9  =  81
---------------------
0
1
2
3
4
5
6
7
8
9
>>> 

▲실행 결과

 

 

 - 파이썬 기초 : 함수 작성 -

#function
#no return
def MySum1():
    a = 10
    b = 20
    print (a+b)

MySum1()

#yes return
def MySum2():
    a = 10
    b = 20
    return (a+b)
print (MySum2())

#yes parameter
def MySum3(a, b):
    return (a + b)
print(MySum3(20, 30))
print(MySum3("aaa", "AAA"))

#global variable
a = 100
def MySum4(b):
    global a
    a = 200
    return (a + b)
print(MySum4(300))

#import modulename as alias
#import time
#import RPi.GPIO as GPIO
#import math
#import random

#Save Python file as ~~~~~~.py >> ~~~~~~ : module name
#can call > ~~~~~~.variable / ~~~~~~.function

 

▲함수 작성

 

 

>>> %Run 200708_3.py
30
30
50
aaaAAA
500
>>>

▲실행 결과

 

 - Hello World, LED 점등, 깜빡이기 -

print('Hello')
print('World')
import random
for x in range(1, 10):
    random_number = random.randint(1, 6) #1 ~ 6
    print(random_number)

▲1.Hello World.py

▲실행 결과

 

 

 

import RPi.GPIO as GPIO
import time

GPIO.setmode(GPIO.BCM) #BCM : 확장보드의 이름대로 핀번호를 준다

GPIO.setup(4, GPIO.OUT, initial=GPIO.LOW)
#7번 핀을 OUT (출력) 목적으로 사용하며 초기 값은 LOW 상태로 시작하도록 설정함

GPIO.output(4, GPIO.HIGH)
#4번 핀에 HIGH 상태로 출력함

time.sleep(3)

GPIO.cleanup()
#GPIO핀들을 개방시켜줌, 개방시키지 않고 종료하면 다음 실행 시 경고 메시지가 표시됨

▲2.LED.py

 

 

import RPi.GPIO as GPIO #GPIO 모듈 불러오기
import time

GPIO.setmode(GPIO.BCM) #GPIO 옆 번호를 사용

#4 > GPIO04 => 핀번호 7번 (다음부터는 BOARED로 사용)
GPIO.setup(4, GPIO.OUT, initial = GPIO.LOW)

try:
    while (True):
        GPIO.output(4, GPIO.HIGH)
        time.sleep(0.5)
        GPIO.output(4, GPIO.LOW)
        time.sleep(0.5)

except KeyboardInterrupt: #Ctrl + C로 종료
    GPIO.cleanup()

▲3.LED Blink.py