No, not in .Net 3.5. But it shouldn’t be that hard to create your own. public class Tuple<T1, T2> { public T1 First { get; private set; } public T2 Second { get; private set; } internal Tuple(T1 first, T2 second) { First = first; Second = second; } } public static class Tuple { … Read more
I’ve just read this article from the MSDN Magazine: Building Tuple Here are excerpts: The upcoming 4.0 release of Microsoft .NET Framework introduces a new type called System.Tuple. System.Tuple is a fixed-size collection of heterogeneously typed data. Like an array, a tuple has a fixed size that can’t be changed once it … Read more
TL;DR: there’s a method _asdict provided for this. Here is a demonstration of the usage: >>> from collections import namedtuple >>> fields = [‘name’, ‘population’, ‘coordinates’, ‘capital’, ‘state_bird’] >>> Town = namedtuple(‘Town’, fields) >>> funkytown = Town(‘funky’, 300, ‘somewhere’, ‘lipps’, ‘chicken’) >>> funkytown._asdict() {‘name’: ‘funky’, ‘population’: 300, ‘coordinates’: ‘somewhere’, ‘capital’: ‘lipps’, ‘state_bird’: ‘chicken’} This is … Read more
The problem is: we have a std::tuple<T1, T2, …> and we have some function f that we can to call on each element, where f returns an int, and we want to store those results in an array. Let’s start with a concrete case: template <typename T> int f(T ) { return sizeof(T); } std::tuple<int, … Read more
You can’t serialize that as json, json has a much less flexible idea about what counts as a dict key than python. You could transform the mapping into a sequence of key, value pairs, something like this: import json def remap_keys(mapping): return [{‘key’:k, ‘value’: v} for k, v in mapping.iteritems()] … json.dumps(remap_keys({(1, 2): ‘foo’})) >>> … Read more
In [2]: min(data, key = lambda t: t[1]) Out[2]: (5, 0.01) or: In [3]: import operator In [4]: min(data, key=operator.itemgetter(1)) Out[4]: (5, 0.01)
Generally, you can use the func(*tuple) syntax. You can even pass a part of the tuple, which seems like what you’re trying to do here: t = (2010, 10, 2, 11, 4, 0, 2, 41, 0) dt = datetime.datetime(*t[0:7]) This is called unpacking a tuple, and can be used for other iterables (such as lists) … Read more
There’s a good article on the topic in the Python wiki: Why Lists Can’t Be Dictionary Keys. As explained there: What would go wrong if Python allowed using lists as keys, say, using their memory location as the hash? It would cause some unexpected behavior. Lists are generally treated as if their value was derived … Read more
why is a tuple converted to a string when it only contains a single string? a = [(‘a’), (‘b’), (‘c’, ‘d’)] Because those first two elements aren’t tuples; they’re just strings. The parenthesis don’t automatically make them tuples. You have to add a comma after the string to indicate to python that it should be … Read more
l = [ (‘a’, 1), (‘a’, 2), (‘a’, 3), (‘b’, 1), (‘b’, 2), (‘c’, 1), ] d = {} for x, y in l: d.setdefault(x, []).append(y) print d produces: {‘a’: [1, 2, 3], ‘c’: [1], ‘b’: [1, 2]}