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Get column index from column name in python pandas
In R when you need to retrieve a column index based on the name of the column you could do
7 Answers
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Regular expression for letters, numbers and - _
I'm having trouble checking in PHP if a value is is any of the following combinations
6 Answers
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How to concatenate strings in twig
...oncat('http://', app.request.host) }}:
In src/AppBundle/Twig/AppExtension.php
<?php
namespace AppBundle\Twig;
class AppExtension extends \Twig_Extension
{
/**
* {@inheritdoc}
*/
public function getFunctions()
{
return [
new \Twig_SimpleFunction('conca...
How do you get the index of the current iteration of a foreach loop?
...rrently on, MoveNext updates Current to the next object.
The concept of an index is foreign to the concept of enumeration, and cannot be done.
Because of that, most collections are able to be traversed using an indexer and the for loop construct.
I greatly prefer using a for loop in this situation c...
Regular expression for a hexadecimal number?
...
If you're using Perl or PHP, you can replace
[0-9a-fA-F]
with:
[[:xdigit:]]
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Get index of element as child relative to parent
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$("#wizard li").click(function () {
console.log( $(this).index() );
});
However rather than attaching one click handler for each list item it is better (performance wise) to use delegate which would look like this:
$("#wizard").delegate('li', 'click', function () {
console.l...
Have Grunt generate index.html for different setups
...
},
Preprocess:
preprocess : {
dev : {
src : './src/tmpl/index.html',
dest : './dev/index.html'
},
prod : {
src : './src/tmpl/index.html',
dest : '../<%= pkg.version %>/<%= now %>/<%= ver %>/index.html',
options : {
...
Primary key or Unique index?
At work we have a big database with unique indexes instead of primary keys and all works fine.
15 Answers
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SQL Server indexes - ascending or descending, what difference does it make?
When you create an index on a column or number of columns in MS SQL Server (I'm using version 2005), you can specify that the index on each column be either ascending or descending. I'm having a hard time understanding why this choice is even here. Using binary sort techniques, wouldn't a lookup be ...
How to display Base64 images in HTML?
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If you have PHP on the back-end, you can use this code:
$image = 'http://images.itracki.com/2011/06/favicon.png';
// Read image path, convert to base64 encoding
$imageData = base64_encode(file_get_contents($image));
// Format the image...