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Filtering a data frame by values in a column [duplicate]
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The subset command is not necessary. Just use data frame indexing
studentdata[studentdata$Drink == 'water',]
Read the warning from ?subset
This is a convenience function intended for use interactively. For
programming it is bette...
Can I change a column from NOT NULL to NULL without dropping it?
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I tried with alter column and it didn't work with the latest mysql server. I tried with modify column and it worked. Strange...
– Kostas Andrianos
Aug 19 '17 at 15:29
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Unable to install R package in Ubuntu 11.04 [closed]
I'm new to Linux and R.
2 Answers
2
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How to fix Terminal not loading ~/.bashrc on OS X Lion [closed]
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From man bash: -s file True if file exists and has a size greater than zero.
– ckruse
Jan 6 '13 at 11:55
1
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SQL Server. How to refresh the intellisense? [duplicate]
...y an easy fix. In SQL Server 2008 R2, I've just imported a new data table and/or renamed fields in an existing table (it happens either way). When I start to write some SQL, the intellisense doesn't recognize the new field names and starts underlining everything.
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Git conflict markers [duplicate]
...e line (or lines) between the lines beginning <<<<<<< and ====== here:
<<<<<<< HEAD:file.txt
Hello world
=======
... is what you already had locally - you can tell because HEAD points to your current branch or commit. The line (or lines) between the line...
How to get the browser language using JavaScript [duplicate]
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equivalent and more JS-typical: navigator.language || navigator.userLanguage
– Eamon Nerbonne
Sep 11 '12 at 15:06
15...
Remove last commit from remote git repository [duplicate]
...he new HEAD commit
If you want to still have it in your local repository and only remove it from the remote, then you can use:
git push origin +HEAD^:<name of your branch, most likely 'master'>
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Enforcing spaces in string resources [duplicate]
In an Android string resource, how do I enforce a space?
3 Answers
3
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How to return images in flask response? [duplicate]
...the type query parameter. See the documentation for the send_file function and the request object for more information.
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