It should work fine. Don’t use tuple, list or other special names as a variable name. It’s probably what’s causing your problem. >>> l = [4,5,6] >>> tuple(l) (4, 5, 6) >>> tuple=”whoops” # Don’t do this >>> tuple(l) TypeError: ‘tuple’ object is not callable
In a thread on comp.lang.java.help, Hunter Gratzner gives some arguments against the presence of a Pair construct in Java. The main argument is that a class Pair doesn’t convey any semantics about the relationship between the two values (how do you know what “first” and “second” mean ?). A better practice is to write a … Read more
sorted_by_second = sorted(data, key=lambda tup: tup[1]) or: data.sort(key=lambda tup: tup[1]) # sorts in place The default sort mode is ascending. To sort in descending order use the option reverse=True: sorted_by_second = sorted(data, key=lambda tup: tup[1], reverse=True) or: data.sort(key=lambda tup: tup[1], reverse=True) # sorts in place
Named tuples are basically easy-to-create, lightweight object types. Named tuple instances can be referenced using object-like variable dereferencing or the standard tuple syntax. They can be used similarly to struct or other common record types, except that they are immutable. They were added in Python 2.6 and Python 3.0, although there is a recipe for … Read more
Apart from tuples being immutable there is also a semantic distinction that should guide their usage. Tuples are heterogeneous data structures (i.e., their entries have different meanings), while lists are homogeneous sequences. Tuples have structure, lists have order. Using this distinction makes code more explicit and understandable. One example would be pairs of page and … Read more