Juurdepääs elementidele ja operatsioonid ennikutel¶

Ennikus olevaid elemente saab kätte indeksi järgi [] operaatoriga. Indekseerimine algab 0-st.

a_tuple = ("January", "February", "March")
# Index        0          1          2
print(a_tuple[0])  # -> January
print(a_tuple[2])  # -> March

# Tuple from a string
b_tuple = tuple("Technology")  # -> ('T', 'e', 'c', 'h', 'n', 'o', 'l', 'o', 'g', 'y')
print(b_tuple[0])  # -> T
print(b_tuple[4])  # -> n
print(b_tuple[9])  # -> y

# Tuple index must be of type int. The range of index of tuple starts from 0 and ends at the length of tuple - 1.
print(b_tuple[10])  # -> IndexError: tuple index out of range

Python lubab kasutada negatiivset indekseerimist nii järjendites kui ka ennikutes. -1 viitab viimasele elemendile, -2 eelviimasele jne.

c_tuple = ("n", "i", "c", "e")
print(c_tuple[-1])  # -> e
print(c_tuple[-2])  # -> c

Tükeldamise (slice) abil saab ligi kindlale vahemikule ennikus, sarnaselt paljudele teistele andmetüüpidele. Tükeldamine toimub kasutades nurksulge ja koolonit: [start:stop:step].

[start] indeks, kust alustada tükeldamist; selle ärajätmisel eeldab Python, et tükeldamine algab algusest
[stop] elemendi indeks, kus peatuda, kusjuures seda elementi ei arvata vahemikku; vaikimisi viimase elemendini
[step] sammu suurus itereerimisel, vaikimisi on see 1; -1 itereerib elemendid tagurpidi

c_tuple = ("a", "b", "c", "d")

# Range of elements between index 0 and index 2, element at index 2 is excluded
print(c_tuple[0:2])  # -> ('a', 'b')

# [start] can be omitted
print(c_tuple[:2])  # -> ('a', 'b')

print(c_tuple[2:4])  # -> ('c', 'd')

# [stop] can be omitted
print(c_tuple[2:])  # -> ('c', 'd')

# Slicing from start to end, easy way to make a copy
print(c_tuple[:])  # -> ("a", "b", "c", "d")

# By choosing [step] to be -1, we get the reverse of original
print(c_tuple[::-1])  # -> ('d', 'c', 'b', 'a')

Enniku puhul saab kasutada in operaatorit, et kontrollida elemendi olemasolu ennikus.

tup = (123, "hello", 999)
b = "hello" in tup
print(b)  # -> True