Besides what Jeremy said, its main benefit is that it has its own bit of syntactic sugar: the enhanced for-loop. If you have, say, an Iterable<String>, you can do: for (String str : myIterable) { … } Nice and easy, isn’t it? All the dirty work of creating the Iterator<String>, checking if it hasNext(), and … Read more
Well it seems simply zip(s,s.index) works too! For Python-3.x, we need to wrap it with list – list(zip(s,s.index)) To get a tuple of tuples, use tuple() : tuple(zip(s,s.index)). Sample run – In [8]: s Out[8]: a 1 b 2 c 3 dtype: int64 In [9]: list(zip(s,s.index)) Out[9]: [(1, ‘a’), (2, ‘b’), (3, ‘c’)] In [10]: … Read more
Your problem is with this line: number4 = list(cow[n]) It tries to take cow[n], which returns an integer, and make it a list. This doesn’t work, as demonstrated below: >>> a = 1 >>> list(a) Traceback (most recent call last): File “<stdin>”, line 1, in <module> TypeError: ‘int’ object is not iterable >>> Perhaps you … Read more
Calls to itertools.imap() in Python 2 or map() in Python 3 can be replaced by equivalent generator expressions: sum(1 for dummy in it) This also uses a lazy generator, so it avoids materializing a full list of all iterator elements in memory.
This is definitely a bug introduced in Python 3.6.0b1. The iter() implementation recently switched to using _PyObject_FastCall() (an optimisation, see issue 27128), and it must be this call that is breaking this. The same issue arrises with other C classmethod methods backed by Argument Clinic parsing: >>> from asyncio import Task >>> Task.all_tasks() set() >>> … Read more
I think the point is that there is no reason for a getFirst(iterable) in that this could be done with iterable.iterator().next(). Guava makes an excellent attempt to keep the API small and so does not add things that could / should be done easily another way. On the other hand, there is not already a … Read more
Presumably because the Collection interface was introduced in Java 1.2 whereas Iterable appeared only in 1.5, and changing the interface would break all existing implementations.
I am only listing out the equivalents of functions from Enumerable<A>. This is incomplete as of now. I will try to update this later with more. xs.Aggregate(accumFunc) -> xs.reduceLeft(accumFunc) xs.Aggregate(seed, accumFunc) -> xs.foldLeft(seed)(accumFunc) xs.Aggregate(seed, accumFunc, trans) -> trans(xs.foldLeft(seed)(accumFunc)) xs.All(pred) -> xs.forall(pred) xs.Any() -> xs.nonEmpty xs.Any(pred) -> xs.exists(pred) xs.AsEnumerable() -> xs.asTraversable // roughly xs.Average() -> xs.sum … Read more
Use generators rather than lists in cases like that: all(v == 0 for v in values) Edit: all is standard Python built-in. If you want to be efficient Python programmer you should know probably more than half of them (http://docs.python.org/library/functions.html). Arguing that alltrue is better name than all is like arguing that C while should … Read more
There really isn’t a good answer. An iterator in Java specifically applies to a collection of discrete items (objects). You would think that a String, which implements CharSequence, should be a “collection” of discrete characters. Instead, it is treated as a single entity that happens to consist of characters. In Java, it seems that iterators … Read more