Is list of tuple immutable in Python?
Python - TuplesAdvertisements Previous Page Next Page A tuple is a collection of objects which ordered and immutable. Tuples are sequences, just like lists. The differences between tuples and lists are, the tuples cannot be changed unlike lists and tuples use parentheses, whereas lists use square brackets. Show Creating a tuple is as simple as putting different comma-separated values. Optionally you can put these comma-separated values between parentheses also. For example tup1 = ('physics', 'chemistry', 1997, 2000); tup2 = (1, 2, 3, 4, 5 ); tup3 = "a", "b", "c", "d";The empty tuple is written as two parentheses containing nothing tup1 = ();To write a tuple containing a single value you have to include a comma, even though there is only one value tup1 = (50,);Like string indices, tuple indices start at 0, and they can be sliced, concatenated, and so on. Accessing Values in TuplesTo access values in tuple, use the square brackets for slicing along with the index or indices to obtain value available at that index. For example When the above code is executed, it produces the following result tup1[0]: physics tup2[1:5]: [2, 3, 4, 5]Updating TuplesTuples are immutable which means you cannot update or change the values of tuple elements. You are able to take portions of existing tuples to create new tuples as the following example demonstrates Live Demo#!/usr/bin/python tup1 = (12, 34.56); tup2 = ('abc', 'xyz'); # Following action is not valid for tuples # tup1[0] = 100; # So let's create a new tuple as follows tup3 = tup1 + tup2; print tup3;When the above code is executed, it produces the following result (12, 34.56, 'abc', 'xyz')Delete Tuple ElementsRemoving individual tuple elements is not possible. There is, of course, nothing wrong with putting together another tuple with the undesired elements discarded. To explicitly remove an entire tuple, just use the del statement. For example Live Demo#!/usr/bin/python tup = ('physics', 'chemistry', 1997, 2000); print tup; del tup; print "After deleting tup : "; print tup;This produces the following result. Note an exception raised, this is because after del tup tuple does not exist any more Basic Tuples OperationsTuples respond to the + and * operators much like strings; they mean concatenation and repetition here too, except that the result is a new tuple, not a string. In fact, tuples respond to all of the general sequence operations we used on strings in the prior chapter
Indexing, Slicing, and MatrixesBecause tuples are sequences, indexing and slicing work the same way for tuples as they do for strings. Assuming following input L = ('spam', 'Spam', 'SPAM!')
No Enclosing DelimitersAny set of multiple objects, comma-separated, written without identifying symbols, i.e., brackets for lists, parentheses for tuples, etc., default to tuples, as indicated in these short examples Live Demo#!/usr/bin/python print 'abc', -4.24e93, 18+6.6j, 'xyz'; x, y = 1, 2; print "Value of x , y : ", x,y;When the above code is executed, it produces the following result Built-in Tuple FunctionsPython includes the following tuple functions
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