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Using R to list all files with a specified extension
I'm very new to R and am working on updating an R script to iterate through a series of .dbf tables created using ArcGIS and produce a series of graphs.
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How to check if an NSDictionary or NSMutableDictionary contains a key?
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And what if the key does exist, but it's corresponding value is nil?
– Fyodor Soikin
May 6 '10 at 21:30
232
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Hibernate throws org.hibernate.AnnotationException: No identifier specified for entity: com..domain.
Why am I getting this exception?
9 Answers
9
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UIRefreshControl - beginRefreshing not working when UITableViewController is inside UINavigationCont
I've setup a UIRefreshControl in my UITableViewController (which is inside a UINavigationController) and it works as expected (i.e. pull down fires the correct event). However, if I programmatically invoke the beginRefreshing instance method on the refresh control like:
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SQL is null and = null [duplicate]
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In SQL, a comparison between a null value and any other value (including another null) using a comparison operator (eg =, !=, <, etc) will result in a null, which is considered as false for the purposes of a where clause (...
Save and load MemoryStream to/from a file
I am serializing an structure into a MemoryStream and I want to save and load the serialized structure.
9 Answers
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JPA or JDBC, how are they different?
I am learning Java EE and I downloaded the eclipse with glassfish for the same. I saw some examples and also read the Oracle docs to know all about Java EE 5. Connecting to a database was very simple. I opened a dynamic web project, created a session EJB , I used EntityManager and with the get meth...
How to resolve “git did not exit cleanly (exit code 128)” error on TortoiseGit? [closed]
I've run into this serious error while committing, and created a bug report .
14 Answers
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How does git store files?
I just started learning git and to do so I started reading the Git Community Book , and in this book they say that SVN and CVS store the difference between files and that git stores a snapshot of all the files.
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ThreadStatic v.s. ThreadLocal: is generic better than attribute?
[ThreadStatic] is defined using attribute while ThreadLocal<T> uses generic.
Why different design solutions were chosen?
What are the advantages and disadvantages of using generic over attributes in this case?
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