In Java the type of any variable is either a primitive type or a reference type. Generic type arguments must be reference types. Since primitives do not extend Object they cannot be used as generic type arguments for a parametrized type. Instead use the Integer class which is a wrapper for int: If your using Java 7 you can simplify … Read more
Python 3 zip stops when the shorter of foo or bar stops. In Python 3, zip returns an iterator of tuples, like itertools.izip in Python2. To get a list of tuples, use list(zip(foo, bar)). And to zip until both iterators are exhausted, you would use itertools.zip_longest. Python 2 In Python 2, zip returns a list of tuples. This is fine when foo and bar are not massive. If they are both massive then forming zip(foo,bar) is … Read more
Here’s a generator that yields the chunks you want: If you’re using Python 2, you should use xrange() instead of range(): Also you can simply use list comprehension instead of writing a function, though it’s a good idea to encapsulate operations like this in named functions so that your code is easier to understand. Python 3: Python 2 … Read more
In Java, List is an interface. That is, it cannot be instantiated directly. Instead you can use ArrayList which is an implementation of that interface that uses an array as its backing store (hence the name). Since ArrayList is a kind of List, you can easily upcast it: This is in contrast with .NET, where, since version 2.0, List<T> is the default implementation of the IList<T> interface.
You can use the sequence method list.extend to extend the list by multiple values from any kind of iterable, being it another list or any other thing that provides a sequence of values. So you can use list.append() to append a single value, and list.extend() to append multiple values.
This, like it sounds, just takes all the elements of the list and joins them with ‘, ‘.
In list[first:last], last is not included. The 10th element is ls[9], in ls[0:10] there isn’t ls[10].
I am trying to remove the character ‘ from my string by doing the following This gives me the error AttributeError: ‘list’ object has no attribute ‘replace’ Coming from a php background I am unsure what the correct way to do this is?
To get the final value of a list pop’ed, you can do it this way: Keep in mind that pop removes the item, and the list changes length after the pop. Use negative numbers to index from the end of a list that may be changing in size, or just use pop() with no arguments for the … Read more
There is a concurrent list implementation in java.util.concurrent. CopyOnWriteArrayList in particular.