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How does one generate a random number in Apple's Swift language?
... introduces new easy-to-use random functions for many data types.
You can call the random() method on numeric types.
let randomInt = Int.random(in: 0..<6)
let randomDouble = Double.random(in: 2.71828...3.14159)
let randomBool = Bool.random()
...
Oracle query to fetch column names
...tion_schema.COLUMNS is USER_TAB_COLS for tables owned by the current user, ALL_TAB_COLS or DBA_TAB_COLS for tables owned by all users.
Tablespace is not equivalent to a schema, neither do you have to provide the tablespace name.
Providing the schema/username would be of use if you want to query AL...
Computational complexity of Fibonacci Sequence
...ll have depth n and intuitively figure out that this function is asymptotically O(2n). You can then prove your conjecture by induction.
Base: n = 1 is obvious
Assume T(n-1) = O(2n-1), therefore
T(n) = T(n-1) + T(n-2) + O(1) which is equal to
T(n) = O(2n-1) + O(2n-2) + O(1) = O(2n)
However, as ...
Why do I have to access template base class members through the this pointer?
...emplate parameter. Others are deferred until the parameter is known. It's called two-phase compilation, and MSVC doesn't do it but it's required by the standard and implemented by the other major compilers. If you like, the compiler must compile the template as soon as it sees it (to some kind of in...
How do you find the disk size of a Postgres / PostgreSQL table and its indexes
... and index size in terms of bytes/MB/GB/etc , or even better the size for all tables. In Oracle I had a nasty long query that looked at user_lobs and user_segments to give back an answer.
...
Get a list of checked checkboxes in a div using jQuery
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Unnecessary call of constructor var selected = new Array();. Better (cheaper) with var selected = [];
– Pono
Mar 17 '14 at 22:45
...
Unresolved reference issue in PyCharm
...
Manually adding it as you have done is indeed one way of doing this, but there is a simpler method, and that is by simply telling pycharm that you want to add the src folder as a source root, and then adding the sources root to y...
Check if list contains any of another list
...ould be to project parameters to source and then use Intersect which internally uses a HashSet<T> so instead of O(n^2) for the first approach (the equivalent of two nested loops) you can do the check in O(n) :
bool hasMatch = parameters.Select(x => x.source)
.Inte...
`levels
...a functional language and does not like to mutate its objects. But it does allow assignment statements, using replacement functions:
levels(x) <- y
is equivalent to
x <- `levels<-`(x, y)
The trick is, this rewriting is done by <-; it is not done by levels<-. levels<- is just ...
Is there any advantage of using map over unordered_map in case of trivial keys?
... unordered_map.
Something else to keep in mind is that unordered_map generally uses more memory. map just has a few house-keeping pointers, and memory for each object. Contrarily, unordered_map has a big array (these can get quite big in some implementations), and then additional memory for each ob...