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Split column at delimiter in data frame [duplicate]
...b','b|c','x|y'))
library(splitstackshape)
cSplit(df, "FOO", "|")
# ID FOO_1 FOO_2
# 1 11 a b
# 2 12 b c
# 3 13 x y
This particular function also handles splitting multiple columns, even if each column has a different delimiter:
df <- data.frame(ID=11:13,
...
Why is it important to override GetHashCode when Equals method is overridden?
...ot match, they may never be considered equal (Equals will simply never be called).
The GetHashCode() method should reflect the Equals logic; the rules are:
if two things are equal (Equals(...) == true) then they must return the same value for GetHashCode()
if the GetHashCode() is equal, it is not...
Catch Ctrl-C in C
...ote this answer seven years ago. Yes, language standards change. If you really must better the world, please add your new answer but leave mine as is. As the answer has my name on it, I'd prefer it to contain my words too. Thank you.
...
Waiting until two async blocks are executed before starting another block
...
NSLog(@"Block3");
});
// only for non-ARC projects, handled automatically in ARC-enabled projects.
dispatch_release(group);
and could produce output like this:
2012-08-11 16:10:18.049 Dispatch[11858:1e03] Block1
2012-08-11 16:10:18.052 Dispatch[11858:1d03] Block2
2012-08-11 16:10:23.051 Dis...
Should I use the datetime or timestamp data type in MySQL?
...
Timestamps in MySQL are generally used to track changes to records, and are often updated every time the record is changed. If you want to store a specific value you should use a datetime field.
If you meant that you want to decide between using a UNIX ...
Configuring so that pip install can work from github
...oo would be:
foo # the installable package
├── foo
│ ├── __init__.py
│ └── bar.py
└── setup.py
And install from github like:
$ pip install git+ssh://git@github.com/myuser/foo.git
or
$ pip install git+https://github.com/myuser/foo.git@v123
or
$ pip install git+htt...
Escape Character in SQL Server
...(1000)
SET @SQL = 'SELECT * FROM MyTable WHERE Field1 = @Field1'
EXECUTE sp_executesql @SQL, N'@Field1 VARCHAR(10)', 'AAA'
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Why the switch statement cannot be applied on strings?
...
The reason why has to do with the type system. C/C++ doesn't really support strings as a type. It does support the idea of a constant char array but it doesn't really fully understand the notion of a string.
In order to generate the code for a switch statement the compiler must under...
Crash logs generated by iPhone Simulator?
...ept trying a few things in the app and it kept crashing). The crashes were all the same, so it wasn't an issue, but I am wondering if this is generally the case?
– Samik R
Dec 8 '12 at 7:46
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MySQL OPTIMIZE all tables?
...ZE TABLE command which can be used to reclaim unused space in a MySQL install. Is there a way (built-in command or common stored procedure) to run this optimization for every table in the database and/or server install, or is this something you'd have to script up yourself?
...