slicing
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l = [1,2,3,4,5]
x = l[1:2:1]
print(x)
x = slice(1,3,1) #1:3:1
print(type(x))
l = list(range(10))
# l = tuple(range(10))
print(l)
print(l[x])
top_4 = slice(1,3,1)
print(l[top_4])
last_4 = slice(-1,-5,-1)
# print(last_4)
print(l[last_4])
print(l[1:3:1])
s = {1,2,3,4,5,6,7,8,9}
# s[1:3:1]
print(last_4.start)
print(last_4.stop)
print(last_4.step)
print(last_4)
# print(l[10])
top_4 = slice(1,100,1)
print(l[top_4])
l = [1,2,3,4,5,6,7,8,9]
print(l[1:15:3])
print(l[-1:-4:-2])
l = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16] #16
# 0,1,2,3,4,5,6,7,8, 9,10,11,12,13,14,15
# -16,-15,-14,... -3,-2,-1
print(l[1:22:3])
print(l[-3:-12:-3]) #[16-3][16-12]
print(l[13:4:-3])
print(l[3:-5:4])
print(l[14:-14:-4])
print(l[-10:14:3])
print(l[-14:-3:3]) # 2:13
print(l[-13:2:-4]) # 3:2
print(l[::-1])
print(l[-4:-99:-1])
#------------ +step
# if start > len(list) => start = len(list)
print(l[16:99:1])
# if end > len(list) => end = len(list) => until last element of the list
print(l[15:99:1])
print(l[99:99:1])
# if start < 0, start = max(0, len(list) + start)
print(l[-99:12:-1])
print(l[-99:5:1])
print(l[-99:-99:1])
# if end < 0, end = max(0, len(list) + end)
# hint : ending value must be smaller than len(list); otherwise empty list
print(l[-99:-99:1])
print(f' end = -99 : {l[:-99]}')
print("end = -99 : {0}".format(l[:-99]))
print("end = -99 :", l[:-99], "something else")
# if start is missing or None start = 0
# if end is missing or None end = len(list) => until last element of the list
print(l[None:12:1])
print(l[1::])
#------- -Step
# if start > len(list); start = len(list) - 1 => starting from the last element
print(l[99:13:-1])
print(l[99::-1])
# print(l[99:99:1])
# print(l[99:16:1])
# print(l[10:99:1])
# if end > len(list); end = len(list) - 1 + stop at out of bound, []
print(l[15:99:-1])
# if start < 0; start = max(-1, len(list) + start) => start from last if |-vs| > len(list) => empty []
print(l[-3:6:-1])
print(l[-99:6:-1])
print(l[-16:6:-1])
# if end < 0; end = max(-1, len(list) + end) => ending at the beginning of the list
print(l[7:-99:-1])
x = l[-4:-1]
print(x[::-1])
# if start is missing or None; start = len(list) - 1 => from the end of the list
print(l[:5:-1])
# if end is missing or None; end = -1 (index, not positive number) => beginning of the list
print(l[2::-1])
print(l[2::-2])
print(l[::-1])
print(l[-3:-12:-3]) #[#13,..#5] [14,11,8]
print(l)
l[2:4] = (4,5,6,7)
print(l)
l[2:4] = "a"
print(l)
l[2:3] = [7,8]
print(l)
l[2:3] = "ab"
print(l)
del l[5:7]
print(l)
l[2:3] = ["ab"]
print(l)
l[2:3] = ("cd",)
# l[2:3] = ("cd")
print(l)
# l[2:5:2] = ["ab","cde","fgh"]
l[2:7:2] = ["ab","cde","fgh"]
print(l)
l[2:3] = [i**2 for i in range(5) if i != 3]
print(l)
l[2:3] = [i**2 for i in l if type(i) == int]
print(l)
print(16*16)
Python
INFO