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Global and local variables in R
...bles declared inside a function are local to that function. For instance:
foo <- function() {
bar <- 1
}
foo()
bar
gives the following error: Error: object 'bar' not found.
If you want to make bar a global variable, you should do:
foo <- function() {
bar <<- 1
}
foo()
bar...
Where is C not a subset of C++? [closed]
...r enum, its name is immediately accessible without any qualifiers:
struct foo { ... };
foo x; // declare variable
In C, this won't work, because types thus declared live in their own distinct namespaces. Thus, you have to write:
struct foo { ... };
struct foo x; // declare variable
Notice the ...
Can a decorator of an instance method access the class?
...ike for using the decorator with parameters? E.g. @class_decorator('test', foo='bar')
– luckydonald
Dec 13 '19 at 16:36
2
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Determine function name from within that function (without using traceback)
...
import inspect
def foo():
print(inspect.stack()[0][3])
print(inspect.stack()[1][3]) #will give the caller of foos name, if something called foo
share
...
Using DNS to redirect to another URL with a path [closed]
...
if you use AWS, a redirect like
mail.foo.com --> mail.google.com/a/foo.com
can be setup as follows:
in s3, create an empty bucket "mail.foo.com"
under Properties -> Static Website Hosting, set "redirect all requests to: mail.google.com/a/foo.com"
in ro...
Advanced JavaScript: Why is this function wrapped in parentheses? [duplicate]
...ction won't affect the global scope. You could use this instead:
function foo() {
// Some code
}
foo();
But this requires giving a name to the function, which is not always necessary. Using a named function also means at some future point the function could be called again which might not be de...
Grep and Sed Equivalent for XML Command Line Processing
...ng tools to process XML.
Example. q.xml:
<?xml version="1.0"?>
<foo>
text
more text
<textnode>ddd</textnode><textnode a="bv">dsss</textnode>
<![CDATA[ asfdasdsa <foo> sdfsdfdsf <bar> ]]>
</foo>
xml2 < q.xml
/foo=
/fo...
Drop all duplicate rows across multiple columns in Python Pandas
...ates and the keep parameter.
import pandas as pd
df = pd.DataFrame({"A":["foo", "foo", "foo", "bar"], "B":[0,1,1,1], "C":["A","A","B","A"]})
df.drop_duplicates(subset=['A', 'C'], keep=False)
share
|
...
How can I sort arrays and data in PHP?
...dimensional arrays, including arrays of objects
$array = array(
array('foo' => 'bar', 'baz' => 42),
array('foo' => ..., 'baz' => ...),
...
);
If you want to sort $array by the key 'foo' of each entry, you need a custom comparison function. The above sort and related functi...
What is the instanceof operator in JavaScript?
...al inheritance.
For example, let's define a type and a subtype:
function Foo(){ //a Foo constructor
//assign some props
return this;
}
function SubFoo(){ //a SubFoo constructor
Foo.call( this ); //inherit static props
//assign some new props
return this;
}
SubFoo.prototype = ...