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How to rename a single column in a data.frame?
...plyr package, and the rename function.
library(plyr)
df <- data.frame(foo=rnorm(1000))
df <- rename(df,c('foo'='samples'))
You can rename by the name (without knowing the position) and perform multiple renames at once. After doing a merge, for example, you might end up with:
letterid ...
Accessing an SQLite Database in Swift
...error preparing insert: \(errmsg)")
}
if sqlite3_bind_text(statement, 1, "foo", -1, SQLITE_TRANSIENT) != SQLITE_OK {
let errmsg = String(cString: sqlite3_errmsg(db)!)
print("failure binding foo: \(errmsg)")
}
if sqlite3_step(statement) != SQLITE_DONE {
let errmsg = String(cString: sqli...
Is there a pretty print for PHP?
...lt;pre>".print_r($array,true)."</pre>";
Example:
$array=array("foo"=>"999","bar"=>"888","poo"=>array("x"=>"111","y"=>"222","z"=>"333"));
echo "<pre>".print_r($array,true)."</pre>";
Result:
Array
(
[foo] => 999
[bar] => 888
[p...
What does $_ mean in PowerShell?
...e in ForEach-Object or Where-Object you can't use it in something like Get-Foo|Add-Member NoteProperty Bar ($_.SomeProperty) – there's a pipeline involved, but no script block and therefore no $_. (That being said, the PowerShell help also refers to the pipeline for $_. Confusing.)
...
How to diff one file to an arbitrary version in Git?
... works for (sub)directories as well, for example git diff <revision>:foo/ HEAD:foo/.
– user456814
Jul 5 '14 at 18:59
...
How to define an enum with string value?
...e enum like this..
public enum Test : int {
[StringValue("a")]
Foo = 1,
[StringValue("b")]
Something = 2
}
To get back the value from Attrinbute Test.Foo.GetStringValue();
Refer : Enum With String Values In C#
...
How do I extract the contents of an rpm?
...
$ mkdir packagecontents; cd packagecontents
$ rpm2cpio ../foo.rpm | cpio -idmv
$ find .
For Reference: the cpio arguments are
-i = extract
-d = make directories
-m = preserve modification time
-v = verbose
I found the answer over here: lontar's answer
...
Entity Framework DateTime and UTC
...your EF context:
public class MyContext : DbContext
{
public DbSet<Foo> Foos { get; set; }
public MyContext()
{
((IObjectContextAdapter)this).ObjectContext.ObjectMaterialized +=
(sender, e) => DateTimeKindAttribute.Apply(e.Entity);
}
}
Now on any Date...
How to pass optional arguments to a method in C++?
...
I understand, but what if I were to have int foo(int x, int y = 10, int z = 10) and would want to call foo(1,2), so only giving one optional parameter. I did not seem to be able to get it to work myself.
– Gerard
Apr 24 '14 at 16:3...