The sequence of Python reading notes

Sequence sequence

A sequence is a set of sequential elements

There are two types of sequences: tuple (fixed value table; also translated as tuple) and List (table)

>>>S1 = (2, 1.3, ' love ', 5.6, 9,, False) # S1 is a tuple

>>>S2 = [True, 5, ' smile '] # s2 is a list

The main difference between a tuple and a list is that once established,each element of a tuple cannot be changed, and the elements of the list can be changed again.

References to elements

The subscript of the sequence element starts with 0

Other reference methods

Range Reference: Basic style [lower limit: Upper limit: Step length]

As can be seen from the above, the upper limit is not included in the range reference when the upper limit is indicated .

Trailing element reference

>>>print S1[-1] # The last element of a sequence

>>>print S1[-3] # third element of sequence countdown

Similarly, if s1[0:-1], then the last element will not be referenced (again, excluding the upper bound element itself)

string is a tuple

strings are a special element, so you can perform related operations on tuples.

>>>str = ' abcdef '

>>>print Str[2:4]

The sequence of Python reading notes