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What does href expression do?
I have seen the following href used in webpages from time to time. However, I don't understand what this is trying to do or the technique. Can someone elaborate please?
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Relative frequencies / proportions with dplyr
...2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes it easy to progressively roll-up a dataset.
Thus, after the summarise, the last grouping variab...
List of standard lengths for database fields
...recommendation:
If designing a form or database that will accept names from people
with a variety of backgrounds, you should ask yourself whether you
really need to have separate fields for given name and family name.
… Bear in mind that names in some cultures can be quite a lot longe...
How do I find the authoritative name-server for a domain name?
...expire = 604800
minimum = 86400
Authoritative answers can be found from:
stackoverflow.com nameserver = ns52.domaincontrol.com.
stackoverflow.com nameserver = ns51.domaincontrol.com.
The origin (or primary name server on Windows) line tells you that ns51.domaincontrol is the ma...
How can I add new keys to a dictionary?
...(): # Iterates just through value, ignoring the keys
Create a dictionary from two lists
data = dict(zip(list_with_keys, list_with_values))
New to Python 3.5
Creating a merged dictionary without modifying originals:
This uses a new featrue called dictionary unpacking.
data = {**data1, **da...
Array.size() vs Array.length
...
.size() is jQuery's, much probably you're either confusing with or took from someone else who had imported the jQuery library to his project.
If you'd have jQuery imported and you'd write like $(array).size(), it would return the array length.
...
How can I rename a database column in a Ruby on Rails migration?
...tion to add columns with the new name(s) and populate them with the values from the old column name.
class AddCorrectColumnNames < ActiveRecord::Migration
def up
add_column :table, :correct_name_column_one, :string
add_column :table, :correct_name_column_two, :string
puts 'Updatin...
Visual studio long compilation when replacing int with double
...st not external dependencies). Would it be possible that result MSIL bytes from compilation would looks exactly like a pattern of a know malware and thus MsMpEnd would fire up ?
– tigrou
Jun 7 '14 at 20:13
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Absolute positioning ignoring padding of parent
... left: 0;
right: 0;
}
It lets the child element inherit the padding from the parent, then the child can be positioned to match the parents widht and padding.
Also, I am using box-sizing: border-box; for the elements involved.
I have not tested this in all browsers, but it seems to be workin...
Can Rails Routing Helpers (i.e. mymodel_path(model)) be Used in Models?
...
Save yourself from copying your :host option everywhere and set it once in your environment config files: Rails.application.routes.default_url_options[:host] = 'localhost:3000'
– Andrew
Feb 18 '14 at ...