Yes it’s expected. A tuple cannot be changed. A tuple, like a list, is a structure that points to other objects. It doesn’t care about what those objects are. They could be strings, numbers, tuples, lists, or other objects. So doing anything to one of the objects contained in the tuple, including appending to that … Read more
user=> (into {} [[:a 1] [:b 2]]) {:a 1, :b 2}
Use a nested list comprehension: result = [a for tup in y for a in tup] Example: >>> x = range(10) >>> y = [(i,j**2) for i,j in zip(x,x)] >>> [a for tup in y for a in tup] [0, 0, 1, 1, 2, 4, 3, 9, 4, 16, 5, 25, 6, 36, 7, 49, … Read more
Python separates the right-hand side expression from the left-hand side assignment. First the right-hand side is evaluated, and the result is stored on the stack, and then the left-hand side names are assigned using opcodes that take values from the stack again. For tuple assignments with 2 or 3 items, Python just uses the stack … Read more
You can use ast.literal_eval(): Safely evaluate an expression node or a string containing a Python expression. The string or node provided may only consist of the following Python literal structures: strings, numbers, tuples, lists, dicts, booleans, and None. This can be used for safely evaluating strings containing Python expressions from untrusted sources without the need … Read more
Use tuple unpacking: >>> pairs = [(“a”, 1), (“b”, 2), (“c”, 3)] >>> for a, b in pairs: … print a, b … a 1 b 2 c 3 See also: Tuple unpacking in for loops.
You need to construct your function sortGT, so that it compares pairs the way you want it: sortGT (a1, b1) (a2, b2) | a1 < a2 = GT | a1 > a2 = LT | a1 == a2 = compare b1 b2 Using this you get the following results (I used ghci): *Main Data.List> sortBy … Read more
Yes, it’s possible. Because an expression such as this at the end of a function: return a, b Is equivalent to this: return (a, b) And there, you’re really returning a single value: a tuple which happens to have two elements. So it’s ok to have a lambda return a tuple, because it’s a single … Read more
Just use a list comprehension: nested_lst_of_tuples = [tuple(l) for l in nested_lst] Demo: >>> nested_lst = [[‘tom’, ‘cat’], [‘jerry’, ‘mouse’], [‘spark’, ‘dog’]] >>> [tuple(l) for l in nested_lst] [(‘tom’, ‘cat’), (‘jerry’, ‘mouse’), (‘spark’, ‘dog’)]
Check out this entry in the msdn blog. VC++11 doesn’t have support for variadic templates. They have something they call faux variadics. Scroll down and you will see a paragraph on Faux variadics that talks about tuples. On that paragraph they say the default maximum number of parameters is 5. You can increase it to … Read more