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Grouping functions (tapply, by, aggregate) and the *apply family
... is best illustrated with a user-defined function to apply:
# Append ! to string, otherwise increment
myFun <- function(x){
if(is.character(x)){
return(paste(x,"!",sep=""))
}
else{
return(x + 1)
}
}
#A nested list structure
l <- list(a = list(a1 = "Boo", b1 = 2, c...
Can I call a constructor from another constructor (do constructor chaining) in C++?
...meters is using your parameter to call the other constructor: SomeType(string const &s) { /*...*/ } SomeType(char const *pc) : SomeType(string(pc)) { /*...*/ }
– Cyrille Ka
Sep 14 '15 at 18:14
...
What is the difference between the | and || or operators?
...c class Driver {
static int x;
static int y;
public static void main(String[] args)
throws Exception {
System.out.println("using double pipe");
if(setX() || setY())
{System.out.println("x = "+x);
System.out.println("y = "+y);
}
System.out.println("using single ...
how to split the ng-repeat data with three columns using bootstrap
...[1,2,3]; var y = [1,2,3]; console.log(x === y); Deep checking means either stringifying and comparing strings, which is risky because an object may not be stringifiable, or recursively checking each property individually. I think Angular could implement that for filters, but I'm sure there's good re...
How to change the order of DataFrame columns?
... know is that without a header, the default column names are integers, not strings.
– daniel brandstetter
Sep 9 '19 at 23:27
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show 2 more c...
Is type=“text/css” necessary in a tag?
...inked resource. It is purely advisory. The value must be a valid MIME type string.
For external resource links, the type attribute is used as a hint to user agents...
share
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improve this answer
...
Function pointers, Closures, and Lambda
...s C# 3 method:
public Person FindPerson(IEnumerable<Person> people, string name)
{
return people.Where(person => person.Name == name);
}
The lambda expression not only encapsulates the logic ("compare the name") but also the environment, including the parameter (i.e. local variable) ...
PHP memory profiling
...g support since the 2.* version. Please search for the "removed functions" string here: http://www.xdebug.org/updates.php
Removed functions
Removed support for Memory profiling as that didn't work properly.
So I've tried another tool and it worked well for me.
https://github.com/arnaud-lb/php-memo...
In what order do static/instance initializer blocks in Java run?
...("Static block called");
}
}
class Test {
public static void main (String [] args) {
system.out.println(Sub.i);
}
}
The above code outputs 10
Update from an "editor"
The technical explanation for this is in JLS 12.4.1
"A reference to a static field (§8.3.1.1) causes i...
What's the best way to iterate an Android Cursor?
...null, null);
for (Cursor phone : new IterableCursor(phones)) {
String name = phone.getString(phone.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
String phoneNumber = phone.getString(phone.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
...