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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
...
Split string every nth character?
...
i was being serious, I used this code in my binary converter in an emulator, I liked that it was a pythonic for loop haaha but thanks for further breaking down why i enjoy the method!
– Trevor Rudolph
Nov 3 '14 at 1:34
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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...
Performance optimization strategies of last resort [closed]
...tors of floats. Changing the code to carry around the extra empty slot and converting the calculation to floating point from fixed point allowed for a slightly less-accurate but much faster result.
– RBerteig
May 30 '09 at 2:19
...
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...
A std::map that keep track of the order of insertion?
I currently have a std::map<std::string,int> that stores an integer value to an unique string identifier, and I do look up with the string. It does mostly what I want, except for that it does not keep track of the insertion order. So when I iterate the the map to print out the values, they a...
Why is argc not a constant?
...ipulate argv[], so it can't be made const for that reason also.
(Aside: Interestingly, although getopt's prototype suggests it won't modify argv[] but may modify the strings pointed to, the Linux man page indicates that getopt permutes its arguments, and it appears they know they're being naughty...
Is there a Python equivalent to Ruby's string interpolation?
...nd text found in the example in the documentation however. Why the use of convert to string here: %(language)s What does the 3 in '03d' signify? Why after the string is there % \? The assignment of variables (if they are in fact variables) after the print expression confuses me also. Sorry if t...