tuples

Javascript: using tuples as dictionary keys

I have a situation where I want to create a mapping from a tuple to an integer. In python, I would simply use a tuple (a,b) as the key to a dictionary, Does Javascript have tuples? I found that (a,b) in javascript as an expression just returns b (the last item). Apparently this is inherited from C. So, as a workaround, I thought I can...

How do i return a quoted string from a tuple?

I have a tuple of strings that i would want to extract the contents as a quoted string, i.e. tup=('string1', 'string2', 'string3') when i do this main_str = ",".join(tup) #i get main_str = 'string1, string2, string3' #I want the main_str to have something like this main_str = '"string1", "string2", "string3"' Gath ...

Is this expected C# 4.0 Tuple equality behavior?

I'm seeing different behavior between using .Equals and == between two of .NET 4.0's new Tuple<> instances. If I have overridden Equals on the object in the Tuple<> and call .Equals on the Tuples the override of Equals will be called. If I use == on the Tuples the override of Equals is not called. Is that by design and does it make sense...

Languages that allow named tuples

I was wondering if there are any languages that allow for named tuples. Ie: an object with multiple variables of different type and configurable name. Eg: public NamedTuple<double:Speed, int:Distance> CalculateStuff(int arg1, int arg2) var result = CalculateStuffTuple(1,2); Console.WriteLine("Speed is: " + result.Speed.ToString()) Co...

How to pick certain elements of x-tuple returned by a function?

I am a newbie to Python. Consider the function str.partition() which returns a 3-tuple. If I am interested in only elements 0 and 2 of this tuple, what is the best way to pick only certain elements out of such a tuple? I can currently do either: # Introduces "part1" variable, which is useless (part0, part1, part2) = str.partition(' ') ...

Access modifiers on methods using Tuple in C#

On one hand, a tuple is versatile, but on the other, can be less clear. As a best practice, should tuple not be used for the return type of a public method? Similarly, should it not be used for the type of any parameter of a public method? In other words, should it only be used in declarations of protected, internal, and private me...

Fastest way to convert '(-1,0)' into tuple(-1, 0)?

I've got a huge tuple of strings, which are being returned from a program. An example tuple being returned might look like this: ('(-1,0)', '(1,0)', '(2,0)', '(3,0)', '(4,0)', '(5,0)', '(6,0)') I can convert these strings to real tuples (with integers inside), but i am hoping someone knows a nice trick to speed this up. Anything i've ...

In Haskell, how do I recursively manipulate a tuple and preappend a character to the first element in the tuple?

The type of this function is function :: Num a => ([Char],a) -> ([Char],a) My input for this function would be something like function (".'*",0) and the function finds the first '.' or '*' and updates a, by adding 200 or 400 to a's value depending on which character was replaced first. Once something is changed, the rest of the charact...

Python : List of dict, if exists increment a dict value, if not append a new dict

I would like do something like that. list_of_urls = ['http://www.google.fr/', 'http://www.google.fr/', 'http://www.google.cn/', 'http://www.google.com/', 'http://www.google.fr/', 'http://www.google.fr/', 'http://www.google.fr/', 'http://www.google.com/', 'http://www.goo...

Parsing a string which represents a list of tuples

I have strings which look like this one: "(8, 12.25), (13, 15), (16.75, 18.5)" and I would like to convert each of them into a python data structure. Preferably a list (or tuple) of tuples containing a pair of float values. I could do that with eval("(8, 12.25), (13, 15), (16.75, 18.5)") which gives me a tuple of tuples, but I don't ...

Is it possible to unpack a tuple without using variables?

I'm using the os.path.split() function on a path in my program to get the filename and pathname of a file then passing them into another method, but my current solution seems rather ugly: path = os.path.split(somefile) some_class(path[0], path[1]) Is it possible to unpack the path tuple in a cleaner way within the call to some_class? ...

C# 3.0 Tuple Equivalents (for poor men)

I find myself occasionally in C# 3.0 looking for ways to simulate the notion of a tuple. Over time I've had various "poor man's" implementations, here are a few of them: Basic Object Array: object[] poorTuple = new object[]{foo,bar,baz}; // basic object array More Strongly Typed, HoHoHo... KeyValuePair<TypeA, KeyValuePair<TypeB, Typ...

Is there a way to have tuples with named fields in Scala, similar to anonymous classes in C#?

See: http://stackoverflow.com/questions/793415/use-of-anonymous-class-in-c In C# you can write: var e = new { ID = 5, Name= "Prashant" }; assertEquals( 5, e.ID ) But in Scala I end up writing: var e = (5, "Prashant") assertEquals( 5, e._1 ) Scala maintains type safety through the use of generics (as does C#), but loses the readabi...

Is there a tuple data structure in Python

I want to have an 3 item combination like tag, name, and list of values (array) what is the best possible data structure to store such things. Current I am using dictionary, but it only allows 2 items, but easy traversal using for k, v in dict.iteritems(): can we have something similar like: for k, v, x in tuple.iteritems(): ...

Should I make a DateRange object?

Hi. First question ever. A few of my domain objects contain date ranges as a pair of start and end date properties: public class Period { public DateTime EffectiveDate { get; set; } public DateTime ThroughDate { get; set; } } public class Timeline { public DateTime StartDate { get; set; } public DateTime EndDate { get; set;...

Converting a Tuples List into a nested List using Python

I want to convert a tuples list into a nested list using Python. How do I do that? I have a sorted list of tuples (sorted by the second value): [(1, 5), (5, 4), (13, 3), (4, 3), (3, 2), (14, 1), (12, 1), (10, 1), (9, 1), (8, 1), (7, 1), (6, 1), (2, 1)] Now I want it to have like this (second value ignored and nested in lists): [...

Add tuple to list of tuples in Python

I am new to python and don't know the best way to do this. I have a list of tuples which represent points and another list which represents offsets. I need a set of all the combinations that this forms. Here's some code: offsets = [( 0, 0),( 0,-1),( 0, 1),( 1, 0),(-1, 0)] points = [( 1, 5),( 3, 3),( 8, 7)] So my set of combined point...

How do I use this information in Python? I don't know how to use this data-type.

According to the NLTK book, I first apply the grammar, and parse it. grammar = r""" NP: {<DT|PP\$>?<JJ>*<NN>} {<NNP>+} """ cp = nltk.RegexpParser(grammar) chunked_sent = cp.parse(sentence) When I print chunked_sent, I get this: (S i/PRP use/VBP to/TO work/VB with/IN you/PRP a...

Are there any methods included in Scala to convert tuples to lists?

I have a Tuple2 of List[List[String]] and I'd like to be able to convert the tuple to a list so that I can then use List.transpose(). Is there any way to do this? Also, I know it's a Pair, though I'm always a fan of generic solutions. ...

Applying a function to a tuple in Scala

This should be an easy one. How do I apply a function to a tuple in Scala? Viz: scala> def f (i : Int, j : Int) = i + j f: (Int,Int)Int scala> val p = (3,4) p: (Int, Int) = (3,4) scala> f p :6: error: missing arguments for method f in object $iw; follow this method with `_' if you want to treat it as a partially applied function ...