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Subset of rows containing NA (missing) values in a chosen column of a data frame
...olumn (in the example it would be column Var2) has there an 'NA' character string (I will replace it with your second statement), then I would like to choose the entire row to be part of the new data frame.
– John
Nov 2 '11 at 14:29
...
How to fix Python indentation
...s of white-space containing a
<Tab> with new strings of white-space using the new
tabstop value given. If you do not specify a new
tabstop size or it is zero, Vim uses the current value
of 'tabstop...
Delete all the queues from RabbitMQ?
...rn: .*
Apply to: Queues
Definition: expires with value 1 (change type from String to Number)
Save
Checkout Queues tab again
All Queues must be deleted
And don't forget remove policy!!!!!!.
share
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...
How do you run a SQL Server query from PowerShell?
...here is the function that I use:
function Invoke-SQL {
param(
[string] $dataSource = ".\SQLEXPRESS",
[string] $database = "MasterData",
[string] $sqlCommand = $(throw "Please specify a query.")
)
$connectionString = "Data Source=$dataSource; " +
"In...
How to read a local text file?
...
But how can you use the text and put it into a string variable for use elsewhere? (I keep on getting 'undefined' no matter what I do to it.)
– not2qubit
Feb 8 '18 at 8:03
...
Upload artifacts to Nexus, without Maven
...ll verify everything is correct.
* @throws IOException
*/
private static
String closeRepo(final String authInfo, final String profile, final String repo, final String nameAndVersion) throws IOException {
String repoInfo = "{'data':{'stagedRepositoryId':'" + repo + "','description':'Closing " ...
Reflecting parameter name: abuse of C# lambda expressions or syntax brilliance?
...ple
C#:
public class Class1
{
public static void Foo(Func<object, string> f)
{
Console.WriteLine(f.Method.GetParameters()[0].Name);
}
}
F#:
Class1.Foo(fun yadda -> "hello")
Result:
"arg" is printed (not "yadda").
As a result, library designers should either avoi...
Using i and j as variables in Matlab
...note the imaginary unit (1j works too). The only exception is when passing strings to the always-slightly-incompatible Symbolic engine. Strange that help 1i and doc 1i don't work though.
– horchler
Jun 2 '13 at 23:45
...
Why does the is operator return false when given null?
...
I think null is string returning false is very intuitive. Null means nothing, and it is definitely not a string. So it should return false. While it is a choice the language designers made, it is a very intuitive one when you consider the re...
What are the main purposes of using std::forward and which problems it solves?
...ways passed as a normal reference.
#include <iostream>
#include <string>
#include <utility>
void overloaded_function(std::string& param) {
std::cout << "std::string& version" << std::endl;
}
void overloaded_function(std::string&& param) {
std::cout...