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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...
What's the difference between SortedList and SortedDictionary?
...re any real practical difference between a SortedList<TKey,TValue> and a SortedDictionary<TKey,TValue> ? Are there any circumstances where you would specifically use one and not the other?
...
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...
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 ...
Reshaping data.frame from wide to long format
I have some trouble to convert my data.frame from a wide table to a long table.
At the moment it looks like this:
9 Answe...
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; ...
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 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...
How to get a file or blob from an object URL?
...her methods. When an image is dropped, I'm using URL.createObjectURL to convert to an object URL to display the image. I am not revoking the url, as I do reuse it.
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