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Dynamically select data frame columns using $ and a character value
...and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , nether of these work
...
Select rows of a matrix that meet a condition
...20, ncol = 4)
colnames(m) <- letters[1:4]
The following command will select the first row of the matrix above.
subset(m, m[,4] == 16)
And this will select the last three.
subset(m, m[,4] > 17)
The result will be a matrix in both cases.
If you want to use column names to select columns...
Equivalent of LIMIT and OFFSET for SQL Server?
...nation it's better to write a query like this:
;WITH Results_CTE AS
(
SELECT
Col1, Col2, ...,
ROW_NUMBER() OVER (ORDER BY SortCol1, SortCol2, ...) AS RowNum
FROM Table
WHERE <whatever>
)
SELECT *
FROM Results_CTE
WHERE RowNum >= @Offset
AND RowNum < @Offset +...
How to get the full path of running process?
...
// include the namespace
using System.Management;
var wmiQueryString = "SELECT ProcessId, ExecutablePath, CommandLine FROM Win32_Process";
using (var searcher = new ManagementObjectSearcher(wmiQueryString))
using (var results = searcher.Get())
{
var query = from p in Process.GetProcesses()
...
PowerShell script to return versions of .NET Framework on a machine?
...ame Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release
Based on the MSDN article, you could build a lookup table and return the marketing product version number for releases after 4.5:
$Lookup = @{
378389 = [version]'4.5'
378675 = [...
Android: create a popup that has multiple selection options
... Hello, can you also show how I can set actions for specific item selections? Example: I want to let the user change the app language by clicking one of those items (probably using if statement).
– Arda Çebi
Feb 7 '18 at 20:11
...
How can I remove or replace SVG content?
...
Here is the solution:
d3.select("svg").remove();
This is a remove function provided by D3.js.
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Eclipse: All my projects disappeared from Project Explorer
...Do File->Import
General->Existing Projects into Workspace
Click the "Select root directory" field and browse to each subfolder in your workspace folder, and import.
For me, this was very tedious, since I had several dozen projects in my workspace, but it's the only solution I found short of ...
What's the purpose of SQL keyword “AS”?
...ynes Yes. Just concatenate (||) the columns and then give it an alias e.g. SELECT foo || bar AS foobar.
– Rupert Madden-Abbott
Dec 10 '18 at 14:26
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How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?
I am trying to dump the contents of a table to a csv file using a MySQL SELECT INTO OUTFILE statement. If I do:
13 Answers...