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How to suppress scientific notation when printing float values?
... I guess by using a variable, give it the desired number of digits, and use it instead of the literal number e.g. f"{a:.{precision}f}"
– Aziz Alto
Nov 15 '19 at 19:39
a...
How to check if a map contains a key in Go?
...ng here
}
Explanation:
if statements in Go can include both a condition and an initialization statement. The example above uses both:
initializes two variables - val will receive either the value of "foo" from the map or a "zero value" (in this case the empty string) and ok will receive a bool ...
How to make an alert dialog fill 90% of screen size?
I can create and display a custom alert dialog just fine but even so I have android:layout_width/height="fill_parent" in the dialog xml it is only as big as the contents.
...
How can I capture the result of var_dump to a string?
...Inwdr I've only ever used var_dump as a convenience feature for debugging, and have certainly never left var_dump statements in production code. I imagine this is typical. In those circumstances, performance is unlikely to be at all relevant.
– Mark Amery
Feb 2...
What is a void pointer in C++? [duplicate]
...ollowing:
It is dealing in unformatted memory. This is what operator new and malloc return: a pointer to a block of memory of a certain size. Since the memory does not have a type (because it does not have a properly constructed object in it yet), it is typeless. IE: void.
It is an opaque handle; ...
Getting current unixtimestamp using Moment.js
...to get the Unix TimeStamp using Moment.js.
I can find many functions which convert timestamp to date in moment.js.
I know that I can easily get the unix timestamp by using the following JavaScript function: Math.floor(new Date().getTime()/1000) .
...
Throw keyword in function's signature
...ce this, so it has to be checked at runtime, which is usually undesirable. And it is not well supported in any case. (MSVC ignores exception specifications, except throw(), which it interprets as a guarantee that no exception will be thrown.
...
C char array initialization
...o
char buf[10] = {'a', 0, 0, 0, 0, 0, 0, 0, 0, 0};
As you can see, no random content: if there are fewer initializers, the remaining of the array is initialized with 0. This the case even if the array is declared inside a function.
...
How to scale threads according to CPU cores?
...termined the number of processors available, create that number of threads and split up your work accordingly.
Update: To further clarify, a Thread is just an Object in Java, so you can create it just like you would create any other object. So, let's say that you call the above method and find tha...
How to create a MySQL hierarchical recursive query
... (select @pv := '19') initialisation
where find_in_set(parent_id, @pv)
and length(@pv := concat(@pv, ',', id))
Here is a fiddle.
Here, the value specified in @pv := '19' should be set to the id of the parent you want to select all the descendants of.
This will work also if a parent has m...