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Error handling in C code
...g a non-throwing variant.
C++ exceptions are relatively expensive but this downside is mostly overblown for programs making sensible use of exceptions. A program simply shouldn't throw exceptions on a codepath where performance is a concern. It doesn't really matter how fast your program can report ...
Eclipse error “ADB server didn't ACK, failed to start daemon”
... could also be because there are other apps using the same 5037 port. Shut down all services running on port 5037 and try starting ADB.
To check if any application is using port 5037, use this:
netstat -a -n -o |findstr "5037"
Get the PID of the application.
Use Process Explorer to find the Pro...
How to make return key on iPhone make keyboard disappear?
...
After quite a bit of time hunting down something that makes sense, this is what I put together and it worked like a charm.
.h
//
// ViewController.h
// demoKeyboardScrolling
//
// Created by Chris Cantley on 11/14/13.
// Copyright (c) 2013 Chris Cantley...
Struct like objects in Java
...nate in whole pixels any other way. Getters and setters will only slow you down.
On the other hand, with:
public class BankAccount{
public int balance;
}
You might want to change the way a balance is calculated at some point in the future. This should really use getters and setters.
It's al...
Mysql command not found in OS X 10.7
...ile, make sure all the instances are stopped (kill any processes not going down), check nothing is listening the MySQL port 3306 (netstat should help) and try to start MySQL again.
– Hophat Abc
May 14 '12 at 4:21
...
Visual Studio popup: “the operation could not be completed”
...ser" file didn't help like it did last time. I finally managed to track it down to an IIS Express issue. I removed the site from my applicationhost.config and let Visual Studio recreate it, this allowed the project to finally be loaded.
...
How do I close all open tabs at once?
...Note, this isn't my answer. I moved this out of the original non-question down to here.
– mmcdole
Feb 4 '09 at 7:00
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Count number of records returned by group by
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This down side of this solution is that it gives you the answer multiple times (for each combination of column_1, column_2, column_3, column_4). This may or may not be a significant side-effect, depending on how you process the r...
Convert a list to a string in C#
... so perhaps the folks here were just not yet aware of it (other than a few down below)
– Andrew Steitz
Sep 7 '17 at 21:06
...
How to join (merge) data frames (inner, outer, left, right)
... df2:
merge(df1,df2, all.y=TRUE)
you can flip 'em, slap 'em and rub 'em down to get the other two outer joins you asked about :)
Subscript Method
A left outer join with df1 on the left using a subscript method would be:
df1[,"State"]<-df2[df1[ ,"Product"], "State"]
The other combination o...