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How to append rows to an R data frame
...
Not knowing what you are trying to do, I'll share one more suggestion: Preallocate vectors of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, def...
Best way to remove from NSMutableArray while iterating?
.... That may be true (although what about the memory and processing cost of allocating a new array, and discarding the old one?) but even if it's faster it may not be as big a deal as it would be for a naive implementation, because NSArrays do not behave like "normal" arrays. They talk the talk but ...
What's the purpose of git-mv?
...it mv b a
git commit -m "second move"
git log --follow a
commit 81b80f5690deec1864ebff294f875980216a059d
Author: Sergey Orshanskiy <*****@gmail.com>
Date: Sat Oct 12 00:35:58 2013 -0400
second move
commit f284fba9dc8455295b1abdaae9cc6ee941b66e7f
Author: Sergey Orshanskiy <*****@gm...
NSURLRequest setting the HTTP header
...NSMutableURLRequest
NSMutableURLRequest* request = [[[NSMutableURLRequest alloc] initWithURL:url]
autorelease];
[request setValue:VALUE forHTTPHeaderField:@"Field You Want To Set"];
or to add a header:
[request addValue:VALUE forHTTPHeaderField:@"Field You Want T...
What is the difference between a Docker image and a container?
... 266 MB
<none> <none> 4ab0d9120985 3 months ago 486.5 MB
Some things to note:
IMAGE ID is the first 12 characters of the true identifier for an image. You can create many tags of a given image, but their IDs will all be the same (as...
What is the @Html.DisplayFor syntax for?
...
@magic-c0d3r the first m is the page's Model object. That's what's used in the labmda expression
– Don Cheadle
Jan 24 '17 at 22:32
...
Navigation in django
... template
register = template.Library()
@register.tag
def active(parser, token):
args = token.split_contents()
template_tag = args[0]
if len(args) < 2:
raise template.TemplateSyntaxError, "%r tag requires at least one argument" % template_tag
return NavSelectedNode(args[...
How do you discover model attributes in Rails?
...er(id: integer, email: string, encrypted_password: string,
reset_password_token: string, reset_password_sent_at: datetime,
remember_created_at: datetime, sign_in_count: integer,
current_sign_in_at: datetime, last_sign_in_at: datetime,
current_sign_in_ip: string, last_sign_in_ip: string, created_...
How to use RestSharp with async/await
...lt;T> overloads there is one method that does not require a CancellationToken to be specified and there is one that does.
So now on to an actual example on how to use it, which will also show how to use a CancellationToken:
private static async void Main()
{
var client = new RestClient();
...
Best way to do multiple constructors in PHP
...
<?php
class Student
{
public function __construct() {
// allocate your stuff
}
public static function withID( $id ) {
$instance = new self();
$instance->loadByID( $id );
return $instance;
}
public static function withRow( array $row ) {
...