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Drop data frame columns by name
...op=FALSE to keep R from converting your data frame to a vector if you only select a single column. Don't forget that data frames are lists, so list selection (one-dimensional like I did) works perfectly well and always returns a list. Or a data frame in this case, which is why I prefer to use it.
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Resharper- Find all unused classes
... find unused references of a single file by right clicking on the file and selecting the "Find Usages" option. Is there any way I can see or get the list of all the unused classes or files in my project ?
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What's the $unwind operator in MongoDB?
...oDB employs an "NoSQL" approach to data storage, so perish the thoughts of selects, joins, etc. from your mind. The way that it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being sai...
Set selected radio from radio group with a value
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With the help of the attribute selector you can select the input element with the corresponding value. Then you have to set the attribute explicitly, using .attr:
var value = 5;
$("input[name=mygroup][value=" + value + "]").attr('checked', 'checked');
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How to allow to accept only image files?
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That should be the selected answer! It just lack a note saying that you still need to check server-side (because of non supporting browser, but also for security)
– Erdal G.
Dec 19 '15 at 13:40
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How to get the next auto-increment id in mysql
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You can use
SELECT AUTO_INCREMENT
FROM information_schema.tables
WHERE table_name = 'table_name'
AND table_schema = DATABASE( ) ;
or if you do not wish to use information_schema you can use this
SHOW TABLE STATUS LIKE 'table_name'
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How to verify an XPath expression in Chrome Developers tool or Firefox's Firebug?
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In "Elements" panel, press Ctrl+F
In the search box, type in XPath or CSS Selector, if elements are found, they will be highlighted in yellow.
Firefox (since version 75)
Since FF 75 it's possible to use raw xpath query without evaluation xpath expressions, see documentation for more info.
Fir...
IntelliJ and Tomcat.. Howto..?
..., so Idea will know about your tomcat server
3) Go to Deployment tab and select Artifact. Apply
4) In src folder put your servlet (you can try my example for testing purpose)
5) Go to web.xml file and link your's servlet like this
6) In web folder put your's .jsp files (for example hey.jsp...
How to change credentials for SVN repository in Eclipse?
...clipse. Another developer added an SVN repository with his credentials and selected 'Save password'. Now every time I do anything with SVN his cached credentials are used. How can I change them to mine?
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Eclipse copy/paste entire line keyboard shortcut
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Ctrl-Alt-Down: copies current line or selected lines to below
Ctrl-Alt-Up:: copies current line or selected lines to above
Ctrl-Shift-L: brings up a List of shortcut keys
See Windows/Preference->General->Keys.
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