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source of historical stock data [closed]
...hat will not get you very far.
Then, if you need the real stuff (level II order book, all ticks as they have happened at all exchanges) one "affordable", yet excellent option is Nanex. They'll actually ship you a drive with terabytes of data. If I remember right its about $3k-4K per year of data. B...
ActiveRecord: List columns in table from console
...e columns in a table I usually go with this:
Model.column_names.sort.
i.e. Orders.column_names.sort
Sorting the column names makes it easy to find what you are looking for.
For more information on each of the columns use this:
Model.columns.map{|column| [column.name, column.sql_type]}.to_h.
Thi...
Addressing localhost from a VirtualBox virtual machine [closed]
...
In order to be able to save your edits to the hosts file, launch Notepad by right clicking it and choosing "Run As Administrator"
– Noah Sussman
Jun 13 '12 at 21:53
...
How can I list (ls) the 5 last modified files in a directory?
...n of commands to use depends in which direction you want your output to be ordered.
For the newest 5 files ordered from newest to oldest, use head to take the first 5 lines of output:
ls -t | head -n 5
For the newest 5 files ordered from oldest to newest, use the -r switch to reverse ls's sort o...
Why should I use Deque over Stack?
...lso as pointed out in the comments, Stack and Deque have reverse iteration orders:
Stack<Integer> stack = new Stack<>();
stack.push(1);
stack.push(2);
stack.push(3);
System.out.println(new ArrayList<>(stack)); // prints 1, 2, 3
Deque<Integer> deque = new ArrayDeque<>...
combinations between two lists?
...-length tuples, all possible
| orderings, no repeated elements
-----------------------------------------+----------------------------------------
combinations(p, r) | r-length tuples, in sorted order, no
...
Understanding recursion [closed]
... right child, before we did that we recursed the left child.
In fact, the order in which we called the children, and added the current node's value didn't matter at all, because addition is commutative.
Now let's look at an operation where order does matter. We'll use a binary tree of nodes, but t...
AngularJS best practices for module declaration?
...t files at will
you can use the function-form of "use strict";
the loading order of files does not matter as much
Options for sorting your modules and files
This way of declaring and accessing modules makes you very flexible. You can sort modules via function-type (like described in another answe...
python multithreading wait till all threads finished
...hich builds something complex for you. Like a real factory: You give in an order and get a finished product back.
– Aaron Digulla
Aug 15 '12 at 12:34
18
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Where can I find the “clamp” function in .NET?
...er that with double and float, the CompareTo method corresponds to a total order where NaN is less than all other values, including NegativeInfinity. So it is not equivalent to the < operator. If you used < with a floating-point type, you would have to consider how to treat NaN also. This is n...