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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...ata.frame(a = 1:3, b=letters[1:3])
require(sqldf)
a1NotIna2 <- sqldf('SELECT * FROM a1 EXCEPT SELECT * FROM a2')
And the rows which are in both data frames:
a1Ina2 <- sqldf('SELECT * FROM a1 INTERSECT SELECT * FROM a2')
The new version of dplyr has a function, anti_join, for exactly the...
Split a List into smaller lists of N size
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@HaraldCoppoolse the OP didn't ask for selecting, only to split lists
– Phate01
Mar 22 '18 at 16:11
1
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Deprecated: mysql_connect()
... with @:
<?php
$connect = @mysql_connect('localhost','root','');
mysql_select_db('dbname');
?>
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How can I clear an HTML file input with JavaScript?
...it does seem reasonable to provide a simple mechanism for clearing already selecting output. I tried using an empty string but it did not work in all browsers, NULL worked in all the browsers I tried (Opera, Chrome, FF, IE11+ and Safari).
EDIT:
Please note that setting to NULL works on all browser...
Add a column to a table, if it does not already exist
...onstruct by using the sys.columns table io sys.objects.
IF NOT EXISTS (
SELECT *
FROM sys.columns
WHERE object_id = OBJECT_ID(N'[dbo].[Person]')
AND name = 'ColumnName'
)
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vim command to restructure/force text to 80 columns
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And it also works with visual selections. Ie something like: V}gq. In this way you see what you are going to format before actually formatting it.
– Plouff
Dec 2 '14 at 11:09
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CSS Input with width: 100% goes outside parent's bound
...il" class="login-field">
<label for="email" style="-moz-user-select: none;-webkit-user-select: none;" onselectstart="return false;">E-mail address</label>
<span><input name="email" id="email" type="text" /></span>
</div>
<div clas...
How do I get the n-th level parent of an element in jQuery?
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this will not work for multiple element selections, a safer way would be: $('.element').first().parents().eq(num);
– zzzzBov
Aug 17 '11 at 13:44
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svn cleanup: sqlite: database disk image is malformed
...ould be a solution:
right mouse click over project
team -> disconnect
Select: Also delete ...
Now, re-connect again:
right mouse click over project
team -> Share project
select your repositorie: mine SVN ( other case: git, etc)
select your repositorie folder
Note:
On my case, I did a...
C#: How to convert a list of objects to a list of a single property of that object?
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List<string> firstNames = people.Select(person => person.FirstName).ToList();
And with sorting
List<string> orderedNames = people.Select(person => person.FirstName).OrderBy(name => name).ToList();
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