How to change values in a tuple?
It’s possible via: t = (‘275’, ‘54000’, ‘0.0’, ‘5000.0’, ‘0.0’) lst = list(t) lst[0] = ‘300’ t = tuple(lst) But if you’re going to need to change things, you probably are better off keeping it as a list
tuples
Pair/tuple data type in Go
You can do this. It looks more wordy than a tuple, but it’s a big improvement because you get type checking. Edit: Replaced snippet with complete working example, following Nick’s suggestion. Playground link: http://play.golang.org/p/RNx_otTFpk package main import “fmt” func main() { queue := make(chan struct {string; int}) go sendPair(queue) pair := <-queue fmt.Println(pair.string, pair.int) } … Read more
Is Using .NET 4.0 Tuples in my C# Code a Poor Design Decision?
Tuples are great if you control both creating and using them – you can maintain context, which is essential to understanding them. On a public API, however, they are less effective. The consumer (not you) has to either guess or look up documentation, especially for things like Tuple<int, int>. I would use them for private/internal … Read more
What’s the difference between System.ValueTuple and System.Tuple?
What are ValueTuples and why not Tuple instead? A ValueTuple is a struct which reflects a tuple, same as the original System.Tuple class. The main difference between Tuple and ValueTuple are: System.ValueTuple is a value type (struct), while System.Tuple is a reference type (class). This is meaningful when talking about allocations and GC pressure. System.ValueTuple … Read more
How does std::tie work?
In order to clarify the core concept, let’s reduce it to a more basic example. Although std::tie is useful for functions returning (a tuple of) more values, we can understand it just fine with just one value: int a; std::tie(a) = std::make_tuple(24); return a; // 24 Things we need to know in order to go … Read more
Find an element in a list of tuples
If you just want the first number to match you can do it like this: [item for item in a if item[0] == 1] If you are just searching for tuples with 1 in them: [item for item in a if 1 in item]
python tuple to dict
Try: >>> t = ((1, ‘a’),(2, ‘b’)) >>> dict((y, x) for x, y in t) {‘a’: 1, ‘b’: 2}
Getting one value from a tuple
You can write i = 5 + tup()[0] Tuples can be indexed just like lists. The main difference between tuples and lists is that tuples are immutable – you can’t set the elements of a tuple to different values, or add or remove elements like you can from a list. But other than that, in … Read more
Why can tuples contain mutable items?
That’s an excellent question. The key insight is that tuples have no way of knowing whether the objects inside them are mutable. The only thing that makes an object mutable is to have a method that alters its data. In general, there is no way to detect this. Another insight is that Python’s containers don’t … Read more
Convert a namedtuple into a dictionary
TL;DR: there’s a method _asdict provided for this. Here is a demonstration of the usage: >>> fields = [‘name’, ‘population’, ‘coordinates’, ‘capital’, ‘state_bird’] >>> Town = collections.namedtuple(‘Town’, fields) >>> funkytown = Town(‘funky’, 300, ‘somewhere’, ‘lipps’, ‘chicken’) >>> funkytown._asdict() OrderedDict([(‘name’, ‘funky’), (‘population’, 300), (‘coordinates’, ‘somewhere’), (‘capital’, ‘lipps’), (‘state_bird’, ‘chicken’)]) This is a documented method of namedtuples, … Read more