Python Web -L04 (For Loop,Slicing)
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a = [1,2,3] # List
for i in a:
print(i)
a = 1,2,3 # Tuple
for i in a:
print(i)
a = {1,2,3} # Set
for i in a:
print(i)
a = {'Name': 1, 'Age' : 2,'Address' : 3} # Dict.
for i in a:
print(type(i), i)
for i in range(3):
print(type(i), i)
for i in range(1,13,2):
print(type(i), i)
for i in range(-1,-13,-2):
print("Navgative value: ",type(i), i)
# Slicing is python object
list = [0,1,2,3,4,5,6,7,8,9,10,11,12]
print(list[1:13:5])
print(list[-1:-5:-2]) #Result: [12,10]; [-1:-5:-2]-> Navgative value (-5) don't need to -1
list = [10,20,30,40,50]
print("list[-3:] value is", list[-3:])
print("list[::-1] value is", list[::-1])
print("list[0:-1:1] value is", list[0:-1:1])
print("list[0:-1:-1] value is", list[0:-1:-1])
print("list[-1:0:-1] value is", list[-1:0:-1])
list = [1,2,3,4,5]
s = slice(0,100)
print(list[s])
s = slice(0,len(list))
print(list[s])
s = slice(0,len(list) % 4)
print(list[s])
print(list[-3:-1]) # [2:4] 3,4
print(list[-3:0]) # result: []; because navgative num. keep navgative num.
print(list[-99:-1]) # -(index value) > -n = 0
print(list[0:-1]) # result: [1,2,3,4]; 1= 0 position, 5 = -1 position
print(list[-1]) # position
print(list[0:99]) # list[0:5]
# print("string", value)
print("List [-99:-1] value is ", list[-99:-1]) # step 1: max(0, n + (i)) step2: max(0,5+(-99)) [0:-1]
print("List [2:-99] value is ", list[2:-99]) # max(0, 5+(-99)) [2:0] ; same as above
print("List[0:-1] value is ", list[0:-1])
print(list[0:-99]) #result: []
print(list[99::])
print(list[99:]) #list[5:]
print(list[-1::])
print(list[None : 5]) # starting value is None or missing, starting value = 0
print(list[1 : None]) # ending value is None or missing, ending value = n
print(list[::])
print(list[:])
print("list[-99:5:2] value is ", list[-99:5:2]) # list = [1,2,3,4,5], list[0:5:2],result:1,3,55
print(list[0:5:2]) # same as above
print(list[99:0:-1]) # starting value > n & stepping = -ve, starting value = n -1
print(list[1:99:-1]) # ending value > n & stepping = -ve, ending value = n -1=>empty
print(list[:1:-1]) # starting value is missing/None & stepping = -ve, starting = n -1
print(list[1::-1]) # ending value is missing/None & stepping = -ve, ending value = -1-(stepping)
print(list[3::-2]) # ending value is missing/None & stepping = -ve, ending value = -1-(stepping)
print(list[-99:1:-1]) # starting value = -ve & stepping = -ve, starting value = max(0, n + starting value)
print(list[0:1:-1])
print(list[-3::-1])
print(list[4:-5:-1]) # ending value & stepping < 0, ending value = max(0, n + ending value)
print(list[::-1])
del list[:2]
print(list)
str = "Hello world & Happy New Year"
str = str[5::3]
print(str)
list = [1,2,3,4,5]
list.insert(3, [1,2,3])
print(list)
list = [i for i in range(10) if i % 2]
print(list)
def temp1(): # same as line 91
for i in range(10):
if i % 2:
return i
def temp_zip_print(list1,list2):
for pair in zip(list1,list2):
print(pair)
list1 = [1,2,3]
list2 = [4,5,6]
z = zip(list1, list2)
print(type(z), z)
temp_zip_print(list1,list2)
combine_list = [i for pair in zip(list1, list2) for i in pair]
print(combine_list)
def temp2():
for pair in zip(list1, list2):
for i in pair:
print(i)
#return i
temp2()
Python
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