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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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Unpacking a list / tuple of pairs into two lists / tuples [duplicate]
...ifference can be important in some cases (e.g. append to it). So the list1 and list2 in the example should really be tuple1 and tuple2.
– Causality
Feb 29 '16 at 20:40
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How to get Time from DateTime format in SQL?
... get only Time from DateTime column using SQL query
using SQL Server 2005 and 2008
Default output:
17 Answers
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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 print a double with two decimals in Android? [duplicate]
...e of bugs: Use String.format(Locale, ...) instead"
– AndreKR
Jul 15 at 11:22
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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
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