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Split data frame string column into multiple columns
...ing columns will have correct types and improve performance by adding type.convert and fixed arguments (since "_and_" isn't really a regex)
setDT(before)[, paste0("type", 1:2) := tstrsplit(type, "_and_", type.convert = TRUE, fixed = TRUE)]
...
How to read a file without newlines?
...t would help in some circumstances, on my system \r\n line endings are not converted to \n, whether read as text or binary, so os.linesep would work where \n does not. But splitlines is clearly the better choice, in the case you mention where the file does not match the os. Really I mostly mentioned...
:: (double colon) operator in Java 8
...
Usually, one would call the reduce method using Math.max(int, int) as follows:
reduce(new IntBinaryOperator() {
int applyAsInt(int left, int right) {
return Math.max(left, right);
}
});
That requires a lot of syntax for just calling Math.max. That's where lambda ...
Custom ImageView with drop shadow
...This is taken from Romain Guy's presentation at Devoxx, pdf found here.
Paint mShadow = new Paint();
// radius=10, y-offset=2, color=black
mShadow.setShadowLayer(10.0f, 0.0f, 2.0f, 0xFF000000);
// in onDraw(Canvas)
canvas.drawBitmap(bitmap, 0.0f, 0.0f, mShadow);
Hope this helps.
NOTES
Do...
What is the difference between .text, .value, and .value2?
... I would probably use Format to control how the number gets converted to a string: var = Format(Range("a1").Value2, "#")
– Charles Williams
Jan 22 '15 at 13:16
2
...
What does Expression.Quote() do that Expression.Constant() can’t already do?
...xtremely confusing and bug prone.
Long answer:
Consider the following:
(int s)=>(int t)=>s+t
The outer lambda is a factory for adders that are bound to the outer lambda's parameter.
Now, suppose we wish to represent this as an expression tree that will later be compiled and executed. Wh...
POST request via RestTemplate in JSON
...
Can Spring use the message converters to automatically convert the Java Object to json like it did in Restful API with RestTemplate?
– fall
Aug 10 '17 at 10:21
...
How to sort List of objects by some property
...esComparer implements Comparator<ActiveAlarm> {
@Override
public int compare(ActiveAlarm x, ActiveAlarm y) {
// TODO: Handle null x or y values
int startComparison = compare(x.timeStarted, y.timeStarted);
return startComparison != 0 ? startComparison
...
What is the explicit promise construction antipattern and how do I avoid it?
...a programming language.
You should only use deferred objects when you are converting an API to promises and can't do it automatically, or when you're writing aggregation functions that are easier expressed this way.
Quoting Esailija:
This is the most common anti-pattern. It is easy to fall in...
Are static fields inherited?
...
3 in all cases, since the static int total inherited by SomeDerivedClass is exactly the one in SomeClass, not a distinct variable.
Edit: actually 4 in all cases, as @ejames spotted and pointed out in his answer, which see.
Edit: the code in the second ques...
