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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...
Geometric Mean: is there a built-in?
...pplication I had in mind they are the same, but of course this is not generally true. Thus, if you want to include optional propagation of zeros, and treat the length(x) differently in the case of NA removal, the following is a slightly longer alternative to the function above.
gm_mean = function(x...
Getting the object's property name
...
More specifically, Object.keys(obj) returns an array of property names, i.e. keys, belonging to the passed in obj.
– a learner has no name
Mar 26 '16 at 12:43
...
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...
git + LaTeX workflow
...ve my work computer and my laptop, and I work on them both. I need to keep all the files synchronized between the two computers, and also would like to keep a revision history. I chose git as my DVCS, and I'm hosting my repository on my server. I'm also using Kile + Okular to do the editing. Kile do...
Does SQLAlchemy have an equivalent of Django's get_or_create?
...
That's basically the way to do it, there is no shortcut readily available AFAIK.
You could generalize it ofcourse:
def get_or_create(session, model, defaults=None, **kwargs):
instance = session.query(model).filter_by(**kwargs).firs...
Is it better to use std::memcpy() or std::copy() in terms to performance?
...y.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the m...
Add new field to every document in a MongoDB collection
...field" : 1, "test" : "a" }
EDIT:
In case you want to add a new_field to all your collection, you have to use empty selector, and set multi flag to true (last param) to update all the documents
db.your_collection.update(
{},
{ $set: {"new_field": 1} },
false,
true
)
EDIT:
In the above ...