[python]count_occurrences /degrees_to_rads/*difference

*는 고민했던 문제

 

count_occurrences

def count_occurences(lst, val):
    print(lst.count(val))
    
>> count_occurences([1,21, 2, 1, 2, 3], 1) #2
리스트명.count(세고싶은 인덱스)

degrees_to_rads

 

1도 = 파이/180

x도 = x * 파이 / 180

def degrees_to_rads(degree):
    print(degree * math.pi / 180)
    
>>> degrees_to_rads(180) # ~3.1416

 

*difference

def difference(a,b):
    newb = set(b)
    print([c for c in a if c not in newb])