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How to detect if multiple keys are pressed at once using JavaScript?
... until its script is finished downloading. Putting it ahead of the content allows the content to load beforehand.
B (which is where your interest lies) You can check for one or more keys at a time where /*insert conditional here*/ was, take this example:
if(map[17] && map[16] && map[...
URL rewriting with PHP
...
You can essentially do this 2 ways:
The .htaccess route with mod_rewrite
Add a file called .htaccess in your root folder, and add something like this:
RewriteEngine on
RewriteRule ^/?Some-text-goes-here/([0-9]+)$ /picture.php?id=$1
Thi...
Why is a div with “display: table-cell;” not affected by margin?
...
Cause
From the MDN documentation:
[The margin property] applies to all elements except elements with
table display types other than table-caption, table and inline-table
In other words, the margin property is not applicable to display:table-cell elements.
Solution
Consider using the bo...
Pandas aggregate count distinct
...
How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "use...
How to import the class within the same directory or sub directory?
I have a directory that stores all the .py files.
13 Answers
13
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Insert auto increment primary key to existing table
...ering if it's possible to insert data into the primary key column automatically (I already have 500 rows in DB and want to give them id but I don't want to do it manually). Any thoughts? Thanks a lot.
...
Programmatically Request Access to Contacts
...ss to the address book must be granted before it can be access programmatically. Here is what I ended up doing.
#import <AddressBookUI/AddressBookUI.h>
// Request authorization to Address Book
ABAddressBookRef addressBookRef = ABAddressBookCreateWithOptions(NULL, NULL);
if (ABAddress...
Does R have an assert statement as in python?
...ndition that will throw an error in your program. Here's an example:
Less_Than_8 = function(x) return(x < 8)
for (i in 1:10)
{
print(i)
stopifnot(Less_Than_8(i))
}
This will print the numbers 1 through 8, then print a message that says
Error: Less_Than_8(i) is not TRUE
It would be ni...
Install Gem from Github Branch?
...
You don't need to build the gem locally. In your gemfile you can specify a github source with a ref, branch or tag.
gem 'rails', :git => "git://github.com/rails/rails.git", :ref => "4aded"
gem 'rails', :git => "git://github.com/rails/rails.git", :bra...
Sort JavaScript object by key
...uestion are outdated, never matched implementation reality, and have officially become incorrect now that the ES6/ES2015 spec has been published.
See the section on property iteration order in Exploring ES6 by Axel Rauschmayer:
All methods that iterate over property keys do so in the same ord...