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Remove an entire column from a data.frame in R
Does anyone know how to remove an entire column from a data.frame in R? For example if I am given this data.frame:
6 Answer...
How to make a JTable non-editable
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You can use a TableModel.
Define a class like this:
public class MyModel extends AbstractTableModel{
//not necessary
}
actually isCellEditable() is false by default so you may omit it. (see: http://docs.oracle.com/javase/6/docs/api/javax/swing/ta...
Searching for UUIDs in text with regex
I'm searching for UUIDs in blocks of text using a regex. Currently I'm relying on the assumption that all UUIDs will follow a patttern of 8-4-4-4-12 hexadecimal digits.
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Is bool a native C type?
...ve type is actually called _Bool, while bool is a standard library macro defined in stdbool.h (which expectedly resolves to _Bool). Objects of type _Bool hold either 0 or 1, while true and false are also macros from stdbool.h.
Note, BTW, that this implies that C preprocessor will interpret #if true...
MySQL: ignore errors when importing?
I am importing a fairly large database. The .sql file has almost 1,000,000 lines in it. Problem is that I am getting a syntax error when trying to import the database. It says:
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Remove duplicate elements from array in Ruby
...icate elements and retains all unique elements in the array.
This is one of many beauties of the Ruby language.
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git error: failed to push some refs to remote
For some reason, I can't push now, whereas I could do it yesterday.
Maybe I messed up with configs or something.
39 Answers...
How do you use the ? : (conditional) operator in JavaScript?
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This is a one-line shorthand for an if-else statement. It's called the conditional operator.1
Here is an example of code that could be shortened with the conditional operator:
var userType;
if (userIsYoungerThan18) {
userType = "Minor";
} else {
us...
Strings are objects in Java, so why don't we use 'new' to create them?
...ew String("abcd")] in Java are interned - this means that every time you refer to "abcd", you get a reference to a single String instance, rather than a new one each time. So you will have:
String a = "abcd";
String b = "abcd";
a == b; //True
but if you had
String a = new String("abcd");
Strin...
How do I delete rows in a data frame?
I have a data frame named "mydata" that looks like this this:
8 Answers
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