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Empty arrays seem to equal true and false at the same time
...t (Array is instance of Object in JS) will check if the object is present, and returns true/false.
When you call if (arr == false) you compare values of this object and the primitive false value. Internally, arr.toString() is called, which returns an empty string "".
This is because toString cal...
How can I repeat a character in Bash?
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You can use:
printf '=%.0s' {1..100}
How this works:
Bash expands {1..100} so the command becomes:
printf '=%.0s' 1 2 3 4 ... 100
I've set printf's format to =%.0s which means that it will always print a single = no matter what argument it is given. Therefore it prints 100 =s.
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Using async/await for multiple tasks
....Select(i => DoSomething(1, i, blogClient)).ToArray());
On the other hand, the above code with WaitAll also blocks the threads and your threads won't be free to process any other work till the operation ends.
Recommended Approach
I would prefer WhenAll which will perform your operations asyn...
Could not load file or assembly 'System.Web.Http 4.0.0 after update from 2012 to 2013
...o.
http://www.asp.net/mvc/tutorials/mvc-5/how-to-upgrade-an-aspnet-mvc-4-and-web-api-project-to-aspnet-mvc-5-and-web-api-2
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How does Dijkstra's Algorithm and A-Star compare?
...was looking at what the guys in the Mario AI Competition have been doing and some of them have built some pretty neat Mario bots utilizing the A* (A-Star) Pathing Algorithm.
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Syntax for creating a two-dimensional array
...ry the following:
int[][] multi = new int[5][10];
... which is a short hand for something like this:
int[][] multi = new int[5][];
multi[0] = new int[10];
multi[1] = new int[10];
multi[2] = new int[10];
multi[3] = new int[10];
multi[4] = new int[10];
Note that every element will be initialized...
Fastest way to replace NAs in a large data.table
... data.table , with many missing values scattered throughout its ~200k rows and 200 columns. I would like to re code those NA values to zeros as efficiently as possible.
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Adding new column to existing DataFrame in Python pandas
I have the following indexed DataFrame with named columns and rows not- continuous numbers:
24 Answers
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Why do Lua arrays(tables) start at 1 instead of 0?
I don't understand the rationale behind the decision of this part of Lua. Why does indexing start at 1? I have read (as many others did) this great paper . It seems to me a strange corner of a language that is very pleasant to learn and program. Don't get me wrong, Lua is just great but there has t...
Run an OLS regression with Pandas Data Frame
I have a pandas data frame and I would like to able to predict the values of column A from the values in columns B and C. Here is a toy example:
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