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Convert data.frame column format from character to factor
...r approach
mtcars[, 'cyl'] <- as.factor(mtcars[, 'cyl'])
str(mtcars) # now look at the classes
This also works for character, dates, integers and other classes
Since you're new to R I'd suggest you have a look at these two websites:
R reference manuals:
http://cran.r-project.org/manuals.html...
'heroku' does not appear to be a git repository
...YourAppName
Lastly add git remote:
$ heroku git:remote -a YourAppName
Now you can safely deploy your app with:
$ git push heroku master
You should wait for some time and see if you don't get any error/interrupt on console while deploying. For details look at heroku article.
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How to parse a CSV file using PHP [duplicate]
... @Julix use the accepted answer . This shorter version is nice if you know the imported data will never have linebreaks within a single value, but otherwise the more robust solution is worth the extra lines of code.
– Jordan Lev
May 15 '17 at 3:57
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What are the differences between JSON and JavaScript object? [duplicate]
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First you should know what JSON is:
It is language agnostic data-interchange format.
The syntax of JSON was inspired by the JavaScript Object Literal notation, but there are differences between them.
For example, in JSON all keys must be ...
set up device for development (???????????? no permissions)
...e and the computer.
Reconnect the phone.
Run adb devices to confirm that now it has permission to access the phone.
Please note that it's possible to use , USER="$LOGINNAME" instead of , MODE="0666" in the .rules file, substituting $LOGINNAME for your login name, i.e. what id -nu prints.
In som...
How to split a string and assign it to variables
...rDetail = net.SplitHostPort("0.0.0.1:8080") //Specific for Host and Port
Now use in you code like ServerDetail.Host and ServerDetail.Port
If you don't want to split specific string do it like this:
type ServerDetail struct {
Host string
Port string
}
ServerDetail = strings.S...
Measure the time it takes to execute a t-sql query
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@TheMoot I know I'm late but the MSDN links are perfect for your "[Subject] for Dummies" needs :). Try to take a look at this How To: Use SQL Profiler
– John Odom
Jan 22 '15 at 15:42
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How does the C# compiler detect COM types?
...)
If:
you are "new"ing an interface type, and
the interface type has a known coclass, and
you ARE using the "no pia" feature for this interface
then the code is generated as (IPIAINTERFACE)Activator.CreateInstance(Type.GetTypeFromClsid(GUID OF COCLASSTYPE))
If:
you are "new"ing an interface ...
What is “Service Include” in a csproj file for?
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The good thing about well-known / constant GUIDs is that they are pretty much unique and therefore very easy to search for in Google. Which I did, and found:
this and this, as well as other interesting hits.
It looks like this is actually a known bug ...
What is the difference between HTTP_HOST and SERVER_NAME in PHP?
...erver config. Which one to use depends on what you need it for. You should now however realize that the one is a client-controlled value which may thus not be reliable for use in business logic and the other is a server-controlled value which is more reliable. You however need to ensure that the web...