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Find an item in List by LINQ?
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If you want the index of the element, this will do it:
int index = list.Select((item, i) => new { Item = item, Index = i })
.First(x => x.Item == search).Index;
// or
var tagged = list.Select((item, i) => new { Item = item, Index = i });
int index = (fro...
Sort NSArray of date strings or objects
...Date dateWithString: s2];
return [d1 compare: d2];
}];
I suggest you convert all your strings to dates before sorting not to do the conversion more times than there are date items. Any sorting algorithm will give you more string to date conversions than the number of items in the array (someti...
ArrayBuffer to base64 encoded string
I need an efficient (read native) way to convert an ArrayBuffer to a base64 string which needs to be used on a multipart post.
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How do I expand a tuple into variadic template function's arguments?
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Here's my code if anyone is interested
Basically at compile time the compiler will recursively unroll all arguments in various inclusive function calls <N> -> calls <N-1> -> calls ... -> calls <0> which is the last one and th...
Applying a function to every row of a table using dplyr?
...e is increasingly not recommended, although lots of people seem to find it intuitive. Do yourself a favour and go through Jenny Bryan's Row-oriented workflows in R with the tidyverse material to get a good handle on this topic.
The most straightforward way I have found is based on one of Hadley's e...
Calculate size of Object in Java [duplicate]
...getObjectSize(o);
}
}
Use getObjectSize:
public class C {
private int x;
private int y;
public static void main(String [] args) {
System.out.println(ObjectSizeFetcher.getObjectSize(new C()));
}
}
Source
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How set background drawable programmatically in Android
...dy); is correct.
Another way to achieve it is to use the following:
final int sdk = android.os.Build.VERSION.SDK_INT;
if(sdk < android.os.Build.VERSION_CODES.JELLY_BEAN) {
layout.setBackgroundDrawable(ContextCompat.getDrawable(context, R.drawable.ready) );
} else {
layout.setBackground(C...
Using an integer as a key in an associative array in JavaScript
... saying. However, note that you can not have integer keys. JavaScript will convert the integer to a string. The following outputs 20, not undefined:
var test = {}
test[2300] = 20;
console.log(test["2300"]);
share
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What is the difference between compare() and compareTo()?
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From JavaNotes:
a.compareTo(b):
Comparable interface : Compares values and returns an int which tells if the values compare less than, equal, or greater than.
If your class objects have a natural order, implement the Comparable<T> interface and define this metho...
ArrayList vs List in C#
...eric collection, List<T> implements the generic IEnumerable<T> interface and can be used easily in LINQ (without requiring any Cast or OfType call).
ArrayList belongs to the days that C# didn't have generics. It's deprecated in favor of List<T>. You shouldn't use ArrayList in new...