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MySQL “Group By” and “Order By”
...clauses will only apply to the returned column value, not to the discarded ones.
IMPORTANT UPDATE
Selecting non-aggregate columns used to work in practice but should not be relied upon. Per the MySQL documentation "this is useful primarily when all values in each nonaggregated column not named in th...
Fatal error: unexpectedly found nil while unwrapping an Optional values [duplicate]
...delegate to acquire an already allocated cell, in lieu of allocating a new one.
That's determined by the exclamation mark after AnyObject:
AnyObject!
So, first thing to consider is, what is an "Implicitly Unwrapped Optional"?
The Swift Programming Language tells us:
Sometimes it is cle...
Enumerable.Empty() equivalent for IQueryable
...causes e.g. Union queries to be broken up into multiple queries instead of one.
– NetMage
May 22 '17 at 23:11
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How can I ensure that a division of integers is always rounded up?
...swer right the first time - is to approach the problem carefully, solve it one step at a time, and use good engineering principles in doing so.
Start by reading the specification for what you're trying to replace. The specification for integer division clearly states:
The division rounds the resu...
What is meant by Scala's path-dependent types?
..., giving a sort of type safety that is dependent on values and not types alone.
This might sound like dependent types, but it is more limited. For example, the type of occupied is dependent on the value of Board. Above, the last line doesn't work because the type of c2 is b2.Coordinate, while occup...
What's the role of adapters in Android?
...lass ArrayAdapter<T> extends BaseAdapter implements Filterable {
// One of the constructors
public ArrayAdapter(Context context, int resource, int textViewResourceId, T[] objects) {
init(context, resource, textViewResourceId, Arrays.asList(objects));
}
void manyMoreMethods(){}
}
Lets...
bind event only once
...example, when you bind something to document, you want to unbind only that one event, not all of them.
– Mārtiņš Briedis
Jul 20 '15 at 7:41
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What is the difference between == and Equals() for primitives in C#?
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Remember that, in the code of the question, if one changes int age = 25; to const int age = 25;, then the outcome will change. That is because an implicit conversion from int to short does exist in that case. See Implicit constant expression conversions.
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Html.Partial vs Html.RenderPartial & Html.Action vs Html.RenderAction
...>
In the snippet above, both calls will yield the same result.
While one can store the output of Html.Partial in a variable or return it from a method, one cannot do this with Html.RenderPartial.
The result will be written to the Response stream during execution/evaluation.
This also appl...
How to convert a NumPy array to PIL image applying matplotlib colormap
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Quite a busy one-liner, but here it is:
First ensure your NumPy array, myarray, is normalised with the max value at 1.0.
Apply the colormap directly to myarray.
Rescale to the 0-255 range.
Convert to integers, using np.uint8().
Use Imag...