similar to: working with tables

Dear R experts, since more or less half a year I am using R. In many of my computations I construct huge matrices. Often I do so using 'cbind' on named lists: do.call( 'cbind', list( "Column_A"=list("Row_one"=1.0, "Row_two"=2.0, "Row_three"=3.0), "Column_B"=list("Row_one"=4.0, "Row_two"=5.0,

Hi All, I am trying write a validation rule where I need to ensure that when a certain value is updated or created in a particular columns, a number of other columns columns are unique and that another column does not contain a certain value. I have been able to use the validates_uniqueness_of :column_a (to be updated or inserted) with , :scope => [ :column_b , :column_c , :column_d ]

Hi there, I''m puzzled by this apparently simple query I can''t manage to reassemble using ez_where plugin. cond = Caboose::EZ::Condition.new :my_table do start_on < Time.now any {end_on > Time.now; end_on.nil?} end I keep getting the following result : >> cond.to_sql => ["my_table.start_on < ? AND (my_table.end_on > ?)", Tue May 23

...if that is possible My task is to find the longest streak of continuous days a user participated in a game. Instead of writing an sql function, I chose to use the R's rle function, to get the longest streaks and then update my db table with the results. The (attached) dataframe is something like this: day user_id 2008/11/01 2001 2008/11/01 2002 2008/11/01 2003

So, under Sqlite2, if I want to update a database''s schema, I have to dump the DB, modify the table''s structure, then go and modify EVERY insert statement. The insert statements look like (from memory): INSERT INTO my_table VALUES (''some_id'', ''some_val'', '''', '''', '''', ''some_other

Hello, I have a situation where the foreign key into a table doesn''t correspond to that table''s primary key: my_table ------------- id (pk) name ... other_table -------------- id (pk) my_table_name (fk references my_table(name)) ... I want to be able to say something like: class OtherTable < ActiveRecord::Base belongs_to :my_table, :foreign_key => { :my_table_name

Adding a column to a table just places the column at the end, but I like to keep related columns together. Is there a way to specify where the column is added in a table with migrations? For example, in MySQL you can do: ALTER TABLE my_table ADD COLUMN new_column INT AFTER other_column I was hoping migrations would support something like this: add_column :my_table, :new_column, :integer,

I have not found anything about this except the following from the DBI documentation : Bind variables: the interface is heavily biased towards queries, as opposed > to general > purpose database development. In particular we made no attempt to define > “bind > variables”; this is a mechanism by which the contents of R/S objects are > implicitly > moved to the database during SQL

https://bugzilla.netfilter.org/show_bug.cgi?id=1226 Bug ID: 1226 Summary: Segmentation fault when printing a rule checking byte zero of NFT_PAYLOAD_LL_HEADER Product: nftables Version: unspecified Hardware: x86_64 OS: Debian GNU/Linux Status: NEW Severity: normal Priority: P5

Hi there ! I try to figure out how to do something like this in Rails : SELECT * FROM my_table WHERE name LIKE ''GOGONAM%'' My problem is the % and the quotes. >From now, I do like this : searched_name = params[:name]+''%'' user = MyTable.find(:all, :conditions => ["name LIKE ?", searched_name]) But is there a more gracefull way to do a LIKE

Hello, So I''ve realized one of the columns in a table has to be binary instead of text. However, a straightforward change_column :my_table, :my_column, :binary fails under PostgreSQL (9.x series) The error message being: PGError: ERROR: column "my_column" cannot be cast to type bytea : ALTER TABLE "my_table" ALTER COLUMN "my_column" TYPE bytea Now

Hi guys, I have a situation here. I have my project set to no pluralization due to legacy tables in environment.rb. Now, I have some new tables which I''m starting to pluralize. When I do a generate a scaffold to this new table: script/generate scaffold my_tables table it seems to work out fine for certain sections like http://mysite.com/railsapp/new (which also inserts properly to

How can i run and get the value from the following sql: select avg(my_field) from my_table where which_year=''0506'' and which_week <= 21 and my_foreign_key_id=10 cheers -- Posted via http://www.ruby-forum.com/.

Hi, I am new at R, and I need some help with some basic stuff. I want to do clustering of data. It works perfectly, but now I want to export my file form R to my Linux directory. The problem is that the file is generated only with the cluster numbers, but it does not carry over the identifiers. Let me show you what I did : 1. demo<-read.table("my_table", sep=",",

Hi, Where to put the execute statements in migration scripts? e.g, I would like to create a table and add a foreign_key reference. def self.up ?? execute "alter table ...." create_table :my_table do |t| t.column :user, :string end ?? execute "alter table ...." end Should the execute statement be above the table creation or below the table creation? Logically I

Thank you for help with the first part. The second part I do not understand. All I get is "3" "3". Presumably this is the factor that you refer to. Is there no simple way of extracting the text alone ----- Forwarded Message ---- From: Peter Alspach <PAlspach@hortresearch.co.nz> To: Jabez Wilson <jabezwuk@yahoo.co.uk> Sent: Tuesday, 7 November, 2006 7:46:02 PM

Hi, I have a complex SQL request to perform. I don''t want to manually do the whole query (find_by_sql) because of the complex joins, but I want to use MySQL functions, such as: Model.find(:all, :include => [../..], :conditions => ["(../..) AND YEAR(STR_TO_DATE(my_table.my_row,''%Y-%m-%d %H:%i:%s'')) = #{year})"], :select

dear experts, I reproduced an experiment (questionnaire) some times. The result of the experiment is a vector of 5 factors, say (A,B,C,D,E). In the original article the result is given in 5 pairs of mean and stDev for A .. E, e.g. mean_A=37.4 and sd_A=8.1. The interval for A,B,C,D,E values is 0..50. The original data frame is not available. For a comparison of my results

Hello, For an internal project we were looking for a solution which extends ActiveRecord by an iterator function. Using find(:all) is no fun if you have to process some 10.000 records. Until now there have been two ways of dealing with that scenario: - write your logic a second times (e.g. use stored procedure) - bet on AR plugins which work around that limitation by fetching IDs and

Hello. How can I compute the Bootstrap p-Value for a one- and two sided test, when I have a bootstrap sample of a statistic of 1000 for example? My hypothesis are for example: 1. Two-Sided: H0: mean=0 vs. H1: mean!=0 2. One Sided: H0: mean>=0 vs. H1: mean<0 I hope you can help me Thanks in advance Regards, Andreas