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I am using single table inheritance. class User < ActiveRecord::Base has_many :abc end class Student < User end The student class should not inherit the has_many :abc relationship. How can we override it? Is there a way to remove an association in the derived class? Pankaj --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to

I dont want to delete the records from my tables but just set a column is_deleted to true. What is the best (clean)way to implement this? Is there any way of defining a model which includes only a set of records which satisfy a certain conditions.eg a condition to include the records for which is_deleted is false some thing like this def User << ActiveRecord::Base :conditions=>

Hallo, has anyone here good links abut ansible tutorials for beginners? Thanks Ralf

hi i updated asterisk today via svn no i can'T start asterisk i get core dumps. i have to comment some modules then i can start: noload => format_au.so noload => format_mp3.so noload => format_pcm_alaw.so.so noload => format_pcm_alaw.so compiling was fine just some warnings somebody has any idea? -------------- next part -------------- An HTML attachment was scrubbed...

catched my eyes today "I have written up my experience of creating a two-interface firewall using Shorewall on Debian" http://www.debianplanet.org/node.php?id=1155

I have been reading a paper whereby the authors took values from Sorensons dissimilarity index and values from a percentage similarity index and applies G-Testing to the table of values. This is carried out to assess the differences in spider faunas (Strattton and Uetz, 1979). I like the method but have been trying to work out what function in R to use to get the percentage similarity. I have

For psychologists like me (possibly for others) by far the most time-consuming detail is variable labels. I need them for just about every analysis I do. We can use special packages like Hmisc and its function spss.get to import the labels, but then nearly all the other packages don't respect the labels, even simple things like list. So I find myself either adding them back in at every step or

Dear colleagues, New versions of "R for Beginners" in French and in English are available on CRAN in the Contributed Documentation section. The document is now nearly 60 pages long, and has been completely revised. The description of "objects" and of data manipulation has been completely re-written. The section on graphics has been particularly extended, and includes now an

Hi List, as I''m a real beginner I would be pleased if someone can answer a maybe simple question. I''m looking for a virtaul server system to be used by diffrent entities. As I heard from other solutions there are often (at least small) security problems. Now I would like to know if it''s (at least theoretical possible) that one user from domU_a can access domU_b or

Hi, I've got two vectors with ratings from two coders, like this: x<-c("red", "yellow", "blue", "red") #coder number 1 y<-c("red", "blue", "blue", "red") #coder number 2 I want to find Cohen's Kappa using the wkappa function in the psych package. The only example in the docs is using a matrix, which

Hello, I'm new to the installation R on Linux and I've followed the instructions on the R Installation and Administration Manual and on the FAQs. I also have changed the path at the .bash_profile file but when I try to type R at the shell prompt, it says: Fatal error: R home directory is not defined I've tried many things but all the time it says the same. Any help would be

http://tinyurl.com/ruby-on-rails-tutorial All feedback welcome.

any patient person out there can explain to a total noob how to use a windows usb device, with a windows driver, via wine? according to http://forum.winehq.org/viewtopic.php?t=4154&start=0&postdays=0&postorder=asc&highlight=usb, i have to make some sort of entry in the "dosdevices" directory from your serial port to the com port. i think. no, that's just for modems.

Is there any documentation that instructs a beginner how to configure (and the logic behind) wine and the steps necessary to install windows software? I have the user's guide but it does lack much, particularly what is going on. I am using ubuntu 6.06 and have presumably installed wine correctly. However, I cannot configure the system. A typical error message is, upon invoking winecfg,

Hi, I've been trying to organize my self, and has been making an order list, for beginners (as I am), of practical topics that should be studied to manage a communication node (ISP). Also, each topic should have referred books, urls and materials about it, in order of reading too. Here I ask you for some experienced help, to conform this, or some reference point where start on. The way you

I'm trying to learn how do basic stuff with sieve; I pasted this from a tutorial, it works fine, mail is delivered to 'friends' BUT, what should I do to keep mail in main inbasket as well as, copy to subbasket ? tried 'copy' but failed so far main_script: line 6: error: unknown command 'copy' (only reported once at first occurence). even after I added

Hello folks, Today I have picked up samba again after years of neglection :) I want to be able to integrate our linux boxes in out windows domain. There are 2 reasons for this. The first reason is backup purposes. I want to be able to access some directories on my unix boxes to copy/backup files to my windows boxes. Until now, the linux boxes gzipped and ftp'd the zip files to the windows

Hi. I used R years ago at Uni but haven't touched it since, so I'm back to beginner level now. After looking through the manuals for a while I've come to the conclusion I don't know where to start looking for what I'm looking for, so I decided to ask for help. I've got a fairly simple data frame with an identifier, period and score. There are a few hundred seperate

I am a complete beginner at R and am using the "kmeans" function for the first time... I have a data frame (dat) that is 17 columns * 91 rows (including headers) I have entered the following: cl <- kmeans(dat, 3, 10) plot(dat, col = cl$cluster) points(cl$centers, col = 1:2, pch = 8) the output is 17*17 graphs ... this is not what I was anticipating - I was hoping to get one graph

Hi all, I am wandering.. is it possible to cluster data which is in a single column ? for example.. I have some data as follows: 4013 7362 7585 9304 11879 14785 21795 30500 30669 30924 33988 36975 40422 42911 50501 51593 53729 54338 55497 57337 61993 62601 66229 69815 69933 70760 71340 75921 83972 90134 91061 . . . is it possible to cluster this data since it is in a single column ? I have