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Dynamically select data frame columns using $ and a character value
...alise that $, like everything else in R, (including for instance ( , + , ^ etc) is a function, that takes arguments and is evaluated. df$V1 could be rewritten as
`$`(df , V1)
or indeed
`$`(df , "V1")
But...
`$`(df , paste0("V1") )
...for instance will never work, nor will anything else that...
Where do I find old versions of Android NDK? [closed]
...dows.zip
on the address bar of your browser
The revision names (r7c, r8c etc.) could be found from the ndk download page
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pass post data with window.location.href
...any sensitive / personal data (i.e names, addresses, emails addresses, DOB etc) in either of these.
Session Storage is a more secure option for anything sensitive, it's only accessible to the origin that set the items and also clears as soon as the browser / tab is closed.
IndexDB is a littl...
Calendar returns wrong month [duplicate]
...nths start from zero, like indexes for lists.
Therefore Jan = 0, Feb = 1, etc.
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A python class that acts like dict
..., has a _dict__ which contains all the object attributes (methods, fields, etc). You do not want to mess around with this unless you want to write code that is modifying itself...
– Raik
Feb 8 '19 at 12:49
...
do { … } while (0) — what is it good for? [duplicate]
...{
break;
}
// do something else
if (error) {
break;
}
// etc..
} while (0);
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How does a hash table work?
...e number from 0 to 29,999.
The filing clerks of that time had to quickly fetch and store client records for the working staff. The staff had decided that it would be more efficient to use a hashing methodology to store and retrieve their records.
To file a client record, filing clerks would use t...
What's the best way to store Phone number in Django models
...look at localflavor package (class us.models.PhoneNumberField for US case, etc.)
Otherwise you could inspect the localflavors to get the maximun lenght for all countries. Localflavor also has forms fields you could use in conjunction with the country code to validate the phone number.
...
Project structure for Google App Engine
... datetime
import logging
import time
from google.appengine.api import urlfetch
from google.appengine.ext.webapp import template
from google.appengine.api import users
from google.appengine.ext import webapp
from models import *
class IndexHandler(webapp.RequestHandler):
def get(self):
date =...
rails 3.1.0 ActionView::Template::Error (application.css isn't precompiled)
...ion.css and instead with their custom CSS classes e.g. admin.css, base.css etc.
Solution is to use as mentioned
bundle exec rake assets:precompile
And in stylesheets references just reference application.css
<%= stylesheet_link_tag "application", :media => "all" %>
Since assets pi...