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To find whether a column exists in data frame or not
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Assuming that the name of your data frame is dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
share
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Symfony 2: How do I check if a user is not logged in inside a template?
...wer answers the OP's question, I would like to add more details.
I understand the OP did not want to check roles, but I am including them so other SO users can copy and paste from this in the future. - everytime I google this, I end up here!
Symfony Doc Sources:
http://symfony.com/doc/current/bo...
Select2 dropdown but allow new values by user?
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For version 4+ check this answer below by Kevin Brown
In Select2 3.5.2 and below, you can use something like:
$(selector).select2({
minimumInputLength:1,
"ajax": {
data:function (term, page) {
return { term:term, page:page };
},
dataType:"json",
quietMillis:100,
re...
How to show all shared libraries used by executables in Linux?
...t answer (I've up-voted it) but can you explain the "grep -P '\t.*so'" command? According to man, this interprets the pattern as a perl regexp, but my version of grep doesn't support it (man indicates this is a general issue). What bit of the regexp is perl-specific?
– Bobby Ja...
Can I do a partial revert in GIT
...e reverted files in the staging area. From there, I'd perform a soft reset and add in the changes I really wanted. For an example workflow:
git revert <sha-of-bad-commit> --no-commit
git reset // This gets them out of the staging area
<edit bad file to look like it should, if necessary&g...
Permanently Set Postgresql Schema Path
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(And if you have no admin access to the server)
ALTER ROLE <your_login_role> SET search_path TO a,b,c;
Two important things to know about:
When a schema name is not simple, it needs to be wrapped in double quotes.
T...
ASP.NET MVC: Unit testing controllers that use UrlHelper
...o the client side so it can do a redirection. I'm using Url.RouteUrl(..) and during my unit tests this fails since the Controller.Url parameter is not pre-filled.
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What format string do I use for milliseconds in date strings on iPhone?
...you just get zeros e.g. for the timeIntervalSince1970 of 1415986217.544384 and .SSSSSS you get .544000 so not a great solution.
– malhal
Nov 14 '14 at 17:31
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iOS: Access app-info.plist variables in code
...w.com/a/4059118/1210822 : "CFBundleVersion has been repurposed to be Build and Version is CFBundleShortVersionString", so now for retrieving the version number from plist, we need to use: NSString *version = [[NSBundle mainBundle] objectForInfoDictionaryKey:@"CFBundleShortVersionString"];
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jQuery form serialize - empty string
...m>
will give you in the alert box foo=2.
.serialize() takes the name and the value of the form fields and creates a string like name1=value1&name2=value2. Without a name it cannot create such a string.
Note that name is something different than id. Your form also would have not worked if ...