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Drop unused factor levels in a subsetted data frame
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As a side-effect the function converts the data frame to a list, so the mydf <- droplevels(mydf) solution suggested by Roman Luštrik and Tommy O'Dell below is preferable.
– Johan
May 9 '14 at 10:41
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How to duplicate a whole line in Vim?
...hen you press : in visual mode, it is transformed to '<,'> so it pre-selects the line range the visual selection spanned over. So, in visual mode, :t0 will copy the lines at the beginning.
– Benoit
Jun 30 '12 at 14:17
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How do I format a date with Dart?
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If someone wants to convert a date in string format to some other string format first use DateTime.parse("2019-09-30") then pass it to DateFormat("date pattern").format() like
dateFormate = DateFormat("dd-MM-yyyy").format(DateTime.parse("2019-...
Set environment variables on Mac OS X Lion
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Edit: Here are some instructions for creating a plist file.
Open Xcode
Select File -> New -> New File...
Under Mac OS X select Resources
Choose a plist file
Follow the rest of the prompts
To edit the file, you can Control-click to get a menu and select Add Row. You then can add a key val...
Add default value of datetime field in SQL Server to a timestamp
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This fails with the error message "Unable to convert between [B and TIMESTAMP]". It seems CURRENT_TIMESTAMP is a binary value, not a datetime.
– Sindri Traustason
Oct 18 '13 at 12:37
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Find the PID of a process that uses a port on Windows
...l (Core-compatible) one-liner to ease copypaste scenarios:
netstat -aon | Select-String 8080 | ForEach-Object { $_ -replace '\s+', ',' } | ConvertFrom-Csv -Header @('Empty', 'Protocol', 'AddressLocal', 'AddressForeign', 'State', 'PID') | ForEach-Object { $portProcess = Get-Process | Where-Object Id...
jQuery Ajax error handling, show custom exception messages
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You need to convert the responseText to JSON. Using JQuery:
jsonValue = jQuery.parseJSON( jqXHR.responseText );
console.log(jsonValue.Message);
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jQuery Click fires twice when clicking on label
... This worked for me as i still wanted the radio button to be selected. I just didn't want the event handler do to everything twice.
– chovy
Dec 14 '13 at 1:50
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Inserting image into IPython notebook markdown
... is alanguage with plain text formatting syntax designed so that it can be converted to HTML and many other formats. Markdown is often used to create rich text using a plain text editor. Check out the following link to learn the syntax : github.com/adam-p/markdown-here/wiki/Markdown-Cheatsheet
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MVC 4 @Scripts “does not exist”
...see this topic:
How to add reference to System.Web.Optimization for MVC-3-converted-to-4 app
As many pointed out, restart of VS could be required after the above steps to make this work.
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