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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
Get the index of the object inside an array, matching a condition
... for (let index = 0; index < test.length; index++) {
if (test[index].prop === search) {
break;
}
}
}
console.timeEnd('loop');
As with most optimizations, this should be applied with care and only when actually needed.
...
System.Security.SecurityException when writing to Event Log
...s, where you do not use deployment process to install application.
However if you deploy your application to other machine(s), consider to register event log sources during installation as suggested in SailAvid's and Nicole Calinoiu's answers.
I am using PowerShell function (calling in Octopus Depl...
PG::ConnectionBad - could not connect to server: Connection refused
...stmaster (PID 347) running in data directory "/usr/local/var/postgres"?
If so, rm postmaster.pid
Restart your server. On a mac using launchctl (with homebrew) the following commands will restart the server.
launchctl unload homebrew.mxcl.postgresql.plist
launchctl load -w homebrew.mxcl.postgre...
How can I detect when an Android application is running in the emulator?
I would like to have my code run slightly differently when running on the emulator than when running on a device. ( For example , using 10.0.2.2 instead of a public URL to run against a development server automatically.) What is the best way to detect when an Android application is running in the em...
how to show lines in common (reverse diff)?
...hich I'd like to know the lines in common rather than the lines which are different between them. Command line unix or windows is fine.
...
What Android tools and methods work best to find memory/resource leaks? [closed]
...iew));
System.gc();
}
private void unbindDrawables(View view) {
if (view.getBackground() != null) {
view.getBackground().setCallback(null);
}
if (view instanceof ViewGroup) {
for (int i = 0; i < ((ViewGroup) view).getChildCount(); i++) {
unbindDrawa...
Finding duplicate values in a SQL table
...: you'd need to have MIN(ID) and then delete for ID values not in the last if MIN(ID) values
– gbn
Jun 10 '14 at 9:59
1
...
MySQL offset infinite rows
...s the number of records in the limit, but consider this: What would you do if you got 18,446,744,073,709,551,615 records back? In fact, what would you do if you got 1,000,000,000 records?
Maybe you do want more than one billion records, but my point is that there is some limit on the number you wan...
Uploading Files in ASP.net without using the FileUpload server control
...edFile file = Request.Files["myFile"];
//check file was submitted
if (file != null && file.ContentLength > 0)
{
string fname = Path.GetFileName(file.FileName);
file.SaveAs(Server.MapPath(Path.Combine("~/App_Data/", fname)));
}
}
...