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Factors in R: more than an annoyance?

...a pain, but my theory is that 90% of why they're a pain is because in read.table and read.csv, the argument stringsAsFactors = TRUE by default (and most users miss this subtlety). I say they are useful because model fitting packages like lme4 use factors and ordered factors to differentially fit mod...
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How to validate inputs dynamically created using ng-repeat, ng-show (angular)

I have a table that is created using ng-repeat. I want to add validation to each element in the table. The problem is that each input cell has the same name as the cell above and below it. I attempted to use the {{$index}} value to name the inputs, but despite the string literals in HTML appearing...
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Transparent ARGB hex value

The colors in this table is all not transparent. I guess the value for the A is set to FF . 5 Answers ...
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How to make a transparent UIWebView

I have an app with a UITableView and a corresponding detail view for each row. In the detail view I have to display some text and a background image (text is different for each row, but the image remains the same). The easiest way, in my opinion, is to put the text in an .rtf file and display it i...
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SqlException from Entity Framework - New transaction is not allowed because there are other threads

...for performance for large datasets? If you have a millions records in the table. ToList() will suck them all into memory. I'm running into this very problem and was wondering whether the following would be feasible a)Detach the entity b)Create a new ObjectContext and attach the detached entity to i...
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Laravel 4 Eloquent Query Using WHERE with OR AND OR?

...', '=', $d); })->get(); Will produce a query like: SELECT * FROM <table> WHERE (a='foo' or b='bar') AND (c='john' or d='doe'); share | improve this answer | foll...
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Group by with multiple columns using lambda

... @Jacob - Anonymous types are immutable classes with properly overriden GetHashCode & Equals methods. They where designed for exactly this kind of use case. – Enigmativity Aug 4 '11 at 2:57 ...
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Best way to store time (hh:mm) in a database

I want to store times in a database table but only need to store the hours and minutes. I know I could just use DATETIME and ignore the other components of the date, but what's the best way to do this without storing more info than I actually need? ...
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Get last record in a queryset

... Django Doc: latest(field_name=None) returns the latest object in the table, by date, using the field_name provided as the date field. This example returns the latest Entry in the table, according to the pub_date field: Entry.objects.latest('pub_date') ...
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delete_all vs destroy_all?

I am looking for the best approach to delete records from a table. For instance, I have a user whose user ID is across many tables. I want to delete this user and every record that has his ID in all tables. ...