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Factors in R: more than an annoyance?
...ls(x)
levels(x$Species)
# [1] "setosa"
This is how to keep levels you've selected out from getting in ggplot legends.
Internally, factors are integers with an attribute level character vector (see attributes(iris$Species) and class(attributes(iris$Species)$levels)), which is clean. If you had to ...
Can I protect against SQL injection by escaping single-quote and surrounding user input with single-
...aping quote will be trimmed (in the 21st character). Then the SQL
sSQL = "select * from USERS where username = '" + username + "' and password = '" + password + "'"
combined with the aforementioned malformed username will result in the password already being outside the quotes, and will just con...
count the frequency that a value occurs in a dataframe column
...iple columns in a df
[my_series[c].value_counts() for c in list(my_series.select_dtypes(include=['O']).columns)]
https://stackoverflow.com/a/28192263/786326
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How to generate service reference with only physical wsdl file
...
This may be the easiest method
Right click on the project and select "Add Service Reference..."
In the Address: box, enter the physical path (C:\test\project....) of the downloaded/Modified wsdl.
Hit Go
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How to check if the user can go back in browser history or not
... if the 'beforeunload' fired.
var $window = $(window),
$trigger = $('.select_your_link'),
fallback = 'your_fallback_url';
hasHistory = false;
$window.on('beforeunload', function(){
hasHistory = true;
});
$trigger.on('click', function(){
window.history.go(-1);
setTimeout(...
Is optimisation level -O3 dangerous in g++?
...er versions of GCC have a profile-guided optimization mode that can (IIUC) selectively apply the -O3 optimizations to hot functions -- effectively automating this process.
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How do I detect when someone shakes an iPhone?
... // Put in code here to handle shake
}
if ( [super respondsToSelector:@selector(motionEnded:withEvent:)] )
[super motionEnded:motion withEvent:event];
}
- (BOOL)canBecomeFirstResponder
{ return YES; }
@end
You can easily transform any UIView (even system views) into a view ...
How to change the name of a Django app?
...ete the permissions: delete from auth_permission where content_type_id in (select id from django_content_type where app_label = '<OldAppName>')
Delete content types: delete from django_content_type where app_label = '<OldAppName>'
Rename the folder of the app.
Change any references to y...
In Javascript/jQuery what does (e) mean?
...le you have posted is a click handler which is a MouseEvent
$(<element selector>).click(function(e) {
// does something
alert(e.type); //will return you click
}
DEMO - Mouse Events DEMO uses e.which and e.type
Some useful references:
http://api.jquery.com/category/events/
http://...
How do I fix a merge conflict due to removal of a file in a branch?
...Rescan for changes in Git Gui (F5)
Notice that conflicting file is deleted
Select Stage Changed Files To Commit (Ctrl-I) from Commit menu
Enter a commit comment like "deleted conflicting file"
Commit (ctrl-enter)
Now if you restart the merge it will (hopefully) work.
...