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What does $_ mean in PowerShell?
... the current value in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable will contain the current val...
Convert Python dict into a dataframe
... pairs):
In [11]: pd.DataFrame(d.items()) # or list(d.items()) in python 3
Out[11]:
0 1
0 2012-07-02 392
1 2012-07-06 392
2 2012-06-29 391
3 2012-06-28 391
...
In [12]: pd.DataFrame(d.items(), columns=['Date', 'DateValue'])
Out[12]:
Date DateValue
0 2012-0...
LINQ Aggregate algorithm explained
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1030
The easiest-to-understand definition of Aggregate is that it performs an operation on each elem...
Why is parenthesis in print voluntary in Python 2.7?
...ding.
*This print behavior in Python 2 can be changed to that of Python 3:
from __future__ import print_function
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How to remove specific value from array using jQuery
I have an array that looks like this: var y = [1, 2, 3];
20 Answers
20
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Why use the params keyword?
...
With params you can call your method like this:
addTwoEach(1, 2, 3, 4, 5);
Without params, you can’t.
Additionally, you can call the method with an array as a parameter in both cases:
addTwoEach(new int[] { 1, 2, 3, 4, 5 });
That is, params allows you to use a shortcut when calling...
Problems with lib-icu dependency when installing Symfony 2.3.x via Composer
...;
Intl::getIcuDataVersion();
attention: not needed anymore ( symfony 2.3 has meanwhile been released )
add the minimum stability flag @dev or @rc to your dependency like this please:
composer create-project symfony/framework-standard-edition mynewerproject/ 2.3.*@dev
The default stability i...
Cron job every three days
...
Run it every three days...
0 0 */3 * *
How about that?
If you want it to run on specific days of the month, like the 1st, 4th, 7th, etc... then you can just have a conditional in your script that checks for the current day of the month.
if (((date('j') -...
Python Matplotlib figure title overlaps axes label when using twiny
...er it is a new feature in later versions of matplotlib, but at least for 1.3.1, this is simply:
plt.title(figure_title, y=1.08)
This also works for plt.suptitle(), but not (yet) for plt.xlabel(), etc.
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Centering text in a table in Twitter Bootstrap
... <th>2</th>
<th>2</th>
<th>3</th>
<th>3</th>
<th>3</th>
<th>3</th>
</tr>
</thead>
<tbody>
<tr>
<td colspan="4">Lorem</td>
&...