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Remove duplicated rows using dplyr
...ce(from = 1, to = 1)
Or maybe a variation of unique() that would let you select which
variables to use:
df %>% unique(x, y)
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How can I set the PHP version in PHPStorm?
...ndows:
File -> Settings -> Languages & Frameworks > PHP
then select your PHP version, for example, 7.0
This is very useful when your local system runs PHP 7.0, for example, but production is running PHP 5.5.
That way PhpStorm will warn you which parts will not work in production, show ...
Combine :after with :hover
I want to combine :after with :hover in CSS (or any other pseudo selector). I basically have a list and the item with the selected class has an arrow shape applied using :after . I want the same to be true for objects that are being hovered over but cant quite get it to work. Heres the cod...
Android add placeholder text to EditText
...
In Android Studio you can add Hint (Place holder) through GUI. First select EditText field on designer view. Then Click on Component Tree Left side of IDE (Normally it's there, but it may be there minimized) There you can see Properties of selected EditText. Find Hint field as below Image
T...
Landscape printing from HTML
...y seem to work in IE7 but this is because IE7 will remember the users last selection of landscape or portrait in print preview (only the browser is re-started).
This article does have some suggested work arounds using JavaScript or ActiveX that send keys to the users browser although it they are no...
python pandas remove duplicate columns
...,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
Finally, df.loc[:,[True,True,False]] selects only the...
Best way to get identity of inserted row?
...rator error', GETDATE());
--Display the result set of the table variable.
SELECT NewScrapReasonID, Name, ModifiedDate FROM @MyTableVar;
--Display the result set of the table.
SELECT ScrapReasonID, Name, ModifiedDate
FROM Production.ScrapReason;
GO
...
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...
Simplest way to profile a PHP script
...connect_to_db();
prof_flag("Perform query");
// Get all the data
$select_query = "SELECT * FROM data_table";
$result = mysql_query($select_query);
prof_flag("Retrieve data");
$rows = array();
$found_data=false;
while($r = mysql_fetch_assoc($result))
{
$found_data=tru...
Use tnsnames.ora in Oracle SQL Developer
...s shown in below image.
In the Preferences options expand Database --> select Advanced --> under "Tnsnames Directory" --> Browse the directory where tnsnames.ora present.
Then click on Ok,
as shown in below diagram.
tnsnames.ora available at Drive:\oracle\product\10x.x.x\client_x\NETWORK\A...