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Transposing a 2D-array in JavaScript
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array[0].map((_, colIndex) => array.map(row => row[colIndex]));
map calls a provided callback function once for each element in an array, in order, and constructs a new array from the results. callback is invoked only for indexe...
Cost of len() function
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Calling len() on those data types is O(1) in CPython, the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComple...
How to write a test which expects an Error to be thrown in Jasmine?
... not possible"));
you should be passing a function into the expect(...) call. Your incorrect code:
// incorrect:
expect(parser.parse(raw)).toThrow(new Error("Parsing is not possible"));
is trying to actually call parser.parse(raw) in an attempt to pass the result into expect(...),
...
OnCreateOptionsMenu() not called in Fragment
I have an app which got one activity with 2 fragments placed horizontally.
8 Answers
8...
What's the difference between size_t and int in C++?
...ndly Wikipedia:
The stdlib.h and stddef.h header files define a datatype called size_t which is used to represent the size of an object. Library functions that take sizes expect them to be of type size_t, and the sizeof operator evaluates to size_t.
The actual type of size_t is platform-dependent; ...
How to set specific java version to Maven
On my machine I have two java versions installed: (1.6 and 1.7 installed manually by me). I need both of them for different projects. But for Maven I need 1.7, now my Maven uses 1,6 java version, how can I set Maven to use 1.7?
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Capture screenshot of active window?
I am making a screen capturing application and everything is going fine. All I need to do is capture the active window and take a screenshot of this active window. Does anyone know how I can do this?
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What are the differences between git remote prune, git prune, git fetch --prune, etc
...frustrated about this. The best way to look at is this. There are potentially three versions of every remote branch:
The actual branch on the remote repository
(e.g., remote repo at https://example.com/repo.git, refs/heads/master)
Your snapshot of that branch locally (stored under refs/remotes/...
Renaming columns in pandas
...UMNS
Use the df.rename() function and refer the columns to be renamed. Not all the columns have to be renamed:
df = df.rename(columns={'oldName1': 'newName1', 'oldName2': 'newName2'})
# Or rename the existing DataFrame (rather than creating a copy)
df.rename(columns={'oldName1': 'newName1', 'oldNam...
Why does Go have a “goto” statement
... x = x + 1
}
if x == 2 {
return z
}
x = x - 2
p = (((((x*_gamP[0]+_gamP[1])*x+_gamP[2])*x+_gamP[3])*x+_gamP[4])*x+_gamP[5])*x + _gamP[6]
q = ((((((x*_gamQ[0]+_gamQ[1])*x+_gamQ[2])*x+_gamQ[3])*x+_gamQ[4])*x+_gamQ[5])*x+_gamQ[6])*x + _gamQ[7]
return z * p / q
small:
if x == 0 ...