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  • How to unblend two images from a blend image

    - by gavishna
    I have blended/merged 2 images img1 and img2 with this code which is woking fine.What i want to know is how to obtain the original two images img1 and img2.The code for blending is as under img1=imread('C:\MATLAB7\Picture5.jpg'); img2=imread('C:\MATLAB7\Picture6.jpg'); for i=1:size(img1,1) for j=1:size(img1,2) for k=1:size(img1,3) output(i,j,k)=(img1(i,j,k)+img2(i,j,k))/2; end end end imshow(output,[0 255]);

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  • Optional parens in Ruby for method with uppercase start letter?

    - by RasmusKL
    I just started out using IronRuby (but the behaviour seems consistent when I tested it in plain Ruby) for a DSL in my .NET application - and as part of this I'm defining methods to be called from the DSL via define_method. However, I've run into an issue regarding optional parens when calling methods starting with an uppercase letter. Given the following program: class DemoClass define_method :test do puts "output from test" end define_method :Test do puts "output from Test" end def run puts "Calling 'test'" test() puts "Calling 'test'" test puts "Calling 'Test()'" Test() puts "Calling 'Test'" Test end end demo = DemoClass.new demo.run Running this code in a console (using plain ruby) yields the following output: ruby .\test.rb Calling 'test' output from test Calling 'test' output from test Calling 'Test()' output from Test Calling 'Test' ./test.rb:13:in `run': uninitialized constant DemoClass::Test (NameError) from ./test.rb:19:in `<main>' I realize that the Ruby convention is that constants start with an uppercase letter and that the general naming convention for methods in Ruby is lowercase. But the parens are really killing my DSL syntax at the moment. Is there any way around this issue?

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  • Converting to MVC3 - some views still want 'System.Web.Mvc, Version=1.0.0.0,

    - by justSteve
    I've used the directions from the release notes and have been able to navigate most pages - my unit tests are not comprehensive but most all pass. However...when I attempt to edit an existing or create a new user I'm getting the error pasted below - notice that it's references version=1... - this project started life as a v1 and was converted to mvc2 at the RTM. I'm still working with V2 projects but no longer any v1. Am i due for a GAC cleansing? Server Error in '/' Application. Could not load file or assembly 'System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified. === Pre-bind state information === LOG: User = STUDIO11\mUser LOG: DisplayName = System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35 (Fully-specified) LOG: Appbase = file:///C:/Users/C:\Users\[path to project]/ LOG: Initial PrivatePath = C:\Users\[path to project]\bin Calling assembly : App_Web_qcjylaoc, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null. === LOG: This bind starts in default load context. LOG: Using application configuration file: C:\Users\[path to project]\web.config LOG: Using host configuration file: LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config. LOG: Post-policy reference: System.Web.Mvc, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35 LOG: The same bind was seen before, and was failed with hr = 0x80070002.

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  • vb.net how to start a folder monitor service at runtime and pass on the folder path to monitor?

    - by mazrabul
    hi, I have the following windows service file: Imports System.ServiceProcess Imports System.IO Public Class fswService Dim fsw As FileSystemWatcher Dim lf As StreamWriter Protected Overrides Sub OnStart(ByVal args As String()) ' Add code here to start your service. This method should set things ' in motion so your service can do its work. lf = New StreamWriter(Application.StartupPath & "\fsw_lg.log") fsw = New FileSystemWatcher() fsw.Path = args(0) fsw.IncludeSubdirectories = True fsw.Filter = ".txt" fsw.EnableRaisingEvents = True AddHandler fsw.Created, New FileSystemEventHandler(AddressOf file_created) AddHandler fsw.Changed, New FileSystemEventHandler(AddressOf file_changed) AddHandler fsw.Deleted, New FileSystemEventHandler(AddressOf file_deleted) End Sub Public Sub file_created(ByVal obj As Object, ByVal e As FileSystemEventArgs) lf.WriteLine(Now.ToShortDateString & "-" & Now.ToShortTimeString & "-" & e.FullPath & "-created") End Sub Public Sub file_changed(ByVal obj As Object, ByVal e As FileSystemEventArgs) lf.WriteLine(Now.ToShortDateString & "-" & Now.ToShortTimeString & "-" & e.FullPath & "-changed") End Sub Public Sub file_deleted(ByVal obj As Object, ByVal e As FileSystemEventArgs) lf.WriteLine(Now.ToShortDateString & "-" & Now.ToShortTimeString & "-" & e.FullPath & "-deleted") End Sub Protected Overrides Sub OnStop() lf.Close() End Sub End Class i have the ServiceName set to fswService (same as class name). When I added an installer I also set the ServiceName for the ServiceInstaller1 as fswService. I want to start this service at runtime based on the user setting the path of the folder to be watched. To achieve this I have the following: Dim fsw_controller As New ServiceProcess.ServiceController fsw_controller.Start(fswService) 2 problems: first, intellisense error saying: 'fswService' is a type and cannot be used as an expression. second, I can not figure out a way to pass on to the service the path of the folder to watch (which is stored at My.Settings.userPath). I really thought this is how you start a service. Am I missing something? Your help is, as always, appreciated. Thanks

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  • Either .each do or .all isn't working how I think it should

    - by user1299656
    So whenever someone rates a shop, I want the Shop model to calculate its new average rating and store that in the database (instead of calculating the average every time someone looks at it). So I wrote the segment of code that follows, and it doesn't work. The loop always iterates exactly once, no matter how many shop_ratings in the database exist that have the shop's id as their shop_id. I played around with it a bit and found that every time a new rating is submitted the function is called successfully, but it only runs the loop once and sets the average to what the first rating was. I don't know if the "query" that sets the ratings variable is wrong or if it's the loop that's wrong. class Shop < ActiveRecord::Base has_many :shop_ratings attr_accessible :name, :latitude, :longitude validates_presence_of :name validates_presence_of :latitude validates_presence_of :longitude def distance_to(lat, long) return (self.longitude - long) + (self.latitude - lat) end def find_average total = 0 count = 0 ratings = ShopRating.all(:conditions => {:shop_id => id}) ratings.each do |submission| total = total + submission.rating count = count + 1 end update_attribute :average_rating, total/count end end

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  • How to limit TCP writes to particular size and then block untlil the data is read

    - by ustulation
    {Qt 4.7.0 , VS 2010} I have a Server written in Qt and a 3rd party client executable. Qt based server uses QTcpServer and QTcpSocket facilities (non-blocking). Going through the articles on TCP I understand the following: the original implementation of TCP mentioned the negotiable window size to be a 16-bit value, thus maximum being 65535 bytes. But implementations often used the RFC window-scale-extension that allows the sliding window size to be scalable by bit-shifting to yield a maximum of 1 gigabyte. This is implementation defined. This could have resulted in majorly different window sizes on receiver and sender end as the server uses Qt facilities without hardcoding any window size limit. Client 1st asks for all information it can based on the previous messages from the server before handling the new (accumulating) incoming messages. So at some point Server receives a lot of messages each asking for data of several MB's. This the server processes and puts it into the sender buffer. Client however is unable to handle the messages at the same pace and it seems that client’s receiver buffer is far smaller (65535 bytes maybe) than sender’s transmit window size. The messages thus get accumulated at sender’s end until the sender’s buffer is full too after which the TCP writes on sender would block. This however does not happen as sender buffer is much larger. Hence this manifests as increase in memory consumption on the sender’s end. To prevent this from happening, I used Qt’s socket’s waitForBytesWritten() with timeout set to -1 for infinite waiting period. This as I see from the behaviour blocks the thread writing TCP data until the data has actually been sensed by the receiver’s window (which will happen when earlier messages have been processed by the client at application level). This has caused memory consumption at Server end to be almost negligible. is there a better alternative to this (in Qt) if i want to restrict the memory consumption at server end to say x MB's? Also please point out if any of my understandings is incorrect.

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  • Singleton with eager initialization

    - by jesper
    I have class X that takes much time to initialize itself. I want to make that class singleton and force its creation when rails application starts. I've made the singleton: class X @@instance = nil def self.instance if @@instance.nil? @@instance = X.new puts 'CREATING' end return @@instance end private_class_method :new end The problem is that every time I use this class I see 'CREATING' in logs. I've tried to put creation of class in initializers directory but it doesn't work either.

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  • Rails 2.x provide meaningful error message with http basic authentication

    - by randombits
    I'm using basic http authentication in my rails app via the following code: class ApplicationController < ActionController::Base helper :all # include all helpers, all the time before_filter :authenticate private def authenticate authenticate_or_request_with_http_basic do |username, password| if username.nil? || password.nil? render :inline => %(xml.instruct! :xml, :version => "1.0", :encoding => "UTF-8" xml.errors do xml.error('Could not authenticate you.') end), :type => :builder, :status => 401 end end end end The problem is, if you do a curl http://127.0.0.1:3000/foo/1.xml without providing the -u username:password flag, you get a dead beat response like this: HTTP/1.1 401 Unauthorized Cache-Control: no-cache WWW-Authenticate: Basic realm="Foo" X-Runtime: 1 Content-Type: text/html; charset=utf-8 Content-Length: 27 Server: WEBrick/1.3.1 (Ruby/1.9.1/2010-01-10) Date: Thu, 03 Jun 2010 03:09:18 GMT Connection: Keep-Alive HTTP Basic: Access denied. Is it possible at all to render the inline XML I have above in the event a username and password is not provided by the user?

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  • Ruby's to_s method question (from Axe book 2nd edition)

    - by prosseek
    According to the axe book (2nd edition), we can use to_s as follows. class Song def to_s "Song" end end song = Song.new() song.to_s But, it doesn't give me anything, in order to print something to the stdout, I should run def to_s p "Song" end Is there any change since the ruby 1.8.2 when the book was written for? My ruby version info is 1.8.7 for Mac. ruby 1.8.7 (2009-06-08 patchlevel 173) [universal-darwin10.0]

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  • What is this Hash-like/Tree-like Construct Called?

    - by viatropos
    I want to create a "Config" class that acts somewhere between a hash and a tree. It's just for storing global values, which can have a context. Here's how I use it: Config.get("root.parent.child_b") #=> "value" Here's what the class might look like: class Construct def get(path) # split path by "." # search tree for nodes end def set(key, value) # split path by "." # create tree node if necessary # set tree value end def tree { :root => { :parent => { :child_a => "value", :child_b => "another value" }, :another_parent => { :something => { :nesting => "goes on and on" } } } } end end Is there a name for this kind of thing, somewhere between Hash and Tree (not a Computer Science major)? Basically a hash-like interface to a tree.

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  • C++ Vector vs Array (Time)

    - by vsha041
    I have got here two programs with me, both are doing exactly the same task. They are just setting an boolean array / vector to the value true. The program using vector takes 27 seconds to run whereas the program involving array with 5 times greater size takes less than 1 s. I would like to know the exact reason as to why there is such a major difference ? Are vectors really that inefficient ? Program using vectors #include <iostream> #include <vector> #include <ctime> using namespace std; int main(){ const int size = 2000; time_t start, end; time(&start); vector<bool> v(size); for(int i = 0; i < size; i++){ for(int j = 0; j < size; j++){ v[i] = true; } } time(&end); cout<<difftime(end, start)<<" seconds."<<endl; } Runtime - 27 seconds Program using Array #include <iostream> #include <ctime> using namespace std; int main(){ const int size = 10000; // 5 times more size time_t start, end; time(&start); bool v[size]; for(int i = 0; i < size; i++){ for(int j = 0; j < size; j++){ v[i] = true; } } time(&end); cout<<difftime(end, start)<<" seconds."<<endl; } Runtime - < 1 seconds Platform - Visual Studio 2008 OS - Windows Vista 32 bit SP 1 Processor Intel(R) Pentium(R) Dual CPU T2370 @ 1.73GHz Memory (RAM) 1.00 GB Thanks Amare

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  • JSON is not nested in rails view

    - by SeanGeneva
    I have a several models in a heirarchy, 1:many at each level. Each class is associated only with the class above it and the one below it, ie: L1 course, L2 unit, L3 unit layout, L4 layout fields, L5 table fields (not in code, but a sibling of layout fields) I am trying to build a JSON response of the entire hierarchy. def show @course = Course.find(params[:id]) respond_to do |format| format.html # show.html.erb format.json do @course = Course.find(params[:id]) @units = @course.units.all @unit_layouts = UnitLayout.where(:unit_id => @units) @layout_fields = LayoutField.where(:unit_layout_id => @unit_layouts) response = {:course => @course, :units => @units, :unit_layouts => @unit_layouts, :layout_fields => @layout_fields} respond_to do |format| format.json {render :json => response } end end end end The code is bring back the correct values, but the units, unit_layouts and layout_fields are all nested at the same level under course. I would like them to be nested inside their parent.

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  • VB.NET FileSystemWatcher Multiple Change Events

    - by John
    Hi. I have the following code: Imports System.IO Public Class Blah Public Sub New() InitializeComponent() Dim watcher As New FileSystemWatcher("C:\") watcher.EnableRaisingEvents = True AddHandler watcher.Changed, AddressOf watcher_Changed End Sub Private Sub watcher_Changed(ByVal sender As Object, ByVal e As FileSystemEventArgs) MsgBox(e.FullPath) End Sub End Class When I run it and save changes to a file on my C drive, the code works great, except it executes the watcher_Changed() method four times. Any idea why? The changeType is "4" every time. Thanks.

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  • JS. How to replace html element with another element/text, represented in string?

    - by EL 2002
    I have a problem with replacing html elements. For example, there is a table <table><tr><td id="idTABLE">0</td><td>END</td></tr></table> (it can be div, span, anything) And string in JS script var str='<td>1</td><td>2</td>'; (it can be anything, '123 text', '<span123 element</span 456' or ' <tr<td123</td ' or anything) How can I replace element 'idTABLE' with str? I mean really replace, so <table><tr><td id="__TABLE__">0</td><td>END</td></tr></table> becomes <table><tr><td>1</td><td>2</td><td>END</td></tr></table> //str='<td>1</td><td>2</td>'; <table><tr>123 text<td>END</td></tr></table> //'123 text' <table><tr> tr><td>123</td> <td>END</td></tr></table> //' <tr><td>123</td> ' I tried with createElement, replaceChild, cloneNode, but with no result at all =(

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  • Speed/expensive of SQLite query vs. List.contains() for "in-set" icon on list rows

    - by kpdvx
    An application I'm developing requires that the app main a local list of things, let's say books, in a local "library." Users can access their local library of books and search for books using a remote web service. The app will be aware of other users of the app through this web service, and users can browse other users' lists of books in their library. Each book is identified by a unique bookId (represented as an int). When viewing books returned through a search result or when viewing another user's book library, the individual list row cells need to visually represent if the book is in the user's local library or not. A user can have at most 5,000 books in the library, stored in SQLite on the device (and synchronized with the remote web service). My question is, to determine if the book shown in the list row is in the user's library, would it be better to directly ask SQLite (via SELECT COUNT(*)...) or to maintain, in-memory, a List or int[] array of some sort containing the unique bookIds. So, on each row display do I query SQLite or check if the List or int[] array contains the unique bookId? Because the user can have at most 5,000 books, each bookId occupies 4 bytes so at most this would use ~ 20kB. In thinking about this, and in typing this out, it seems obvious to me that it would be far better for performance if I maintained a list or int[] array of in-library bookIds vs. querying SQLite (the only caveat to maintaining an int[] array is that if books are added or removed I'll need to grow or shrink the array by hand, so with this option I'll most likely use an ArrayList or Vector, though I'm not sure of the additional memory overhead of using Integer objects as opposed to primitives). Opinions, thoughts, suggestions?

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  • Why this search can not generate correct result?

    - by user482742
    Hi, All: Below is to find same customer and if he is in list, the number add one. If he is not in the list, just add him in the list. I use Search function to do this, but failed and generated incorrect records. It can not find the customer or the right number of customers. But if I use For..loop to iterate the list, it does well and can find the customer and add new customer in that for..loop search procedure. (I did not paste for ..loop search procedrue here). Another problem is that there is no difference between setting list.sorted true and false. It seems Search function is not correct. This search function is from an example of delphi textbook. The below is with Delphi 7. Thank you. Procedure Form1.create; begin list:=Tstringlist.create; list.sorted:=true; // Search function will generate exactly Same and Incorrect //records no matter list.sorted is set true or false. list.duplicates:=dupignore; .. end; Procedure addcustomer; var .. begin while p1.MatchAgain do begin //p1 is regular expression customer:=p1.MatchedExpression; if (search(customer)=false) then begin list.Add(customer+'=1'); end; allcustomer:=allcustomer+1; .. end; Function Tform1.search(customer: string): boolean; var fre:string; num:integer; L:integer; R:integer; M: Integer; CompareResult: Integer; found: boolean; begin result:=false; found:=false; L := 0; R := List.Count - 1; while (L <= R) and ( not found ) do begin M := (L + R) div 2; CompareResult := Comparetext(list.Names[m]), customer); if (compareresult=0) then begin fre:=list.ValueFromIndex [m]; num:=strtoint(fre); num:=num+1; list.ValueFromIndex[m]:=inttostr(num); Found := True; Result := true; exit; end else if compareresult > 0 then r := m - 1 else l := m + 1; end; end;

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  • Passing user_id, site_id, and question_id to same table on create...

    - by bgadoci
    I can't seem to figure out how to do this. I am trying to pass four different variables to a single table. To be more specific I am trying to create a "like" in a likes table that also captures the site_id (like an answer), user_id, and the question_id. Here is the set up. class Like < ActiveRecord::Base belongs_to :site belongs_to :user belongs_to :question end I will spare you the reverse, has_many associations but they are there. Here is the likes controller where I think the problem is. class LikesController < ApplicationController def create @user = current_user @site = Site.find(params[:site_id]) @like = @site.likes.create!(params[:like]) @like.user = current_user @like.save respond_to do |format| format.html { redirect_to @site} format.js end end end This code successfully passes the like and site_id but after many different variations of trying I can't get it to pass the question id. Here is my form: /views/sites/_site.html.erb (though the partial is being displayed in the /views/questions/show.html.erb file). <% remote_form_for [site, Like.new] do |f| %> <%= f.hidden_field :site_name, :value => "#{site.name}" %> <%= f.hidden_field :ip_address, :value => "#{request.remote_ip}" %> <%= f.hidden_field :like, :value => "1" %> <%= submit_tag "^" , :class => 'voteup' %> <% end %>

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  • INSERT..ON DUPLICATE KEY UPDATE - but NOT using the duplicate key to compare.

    - by calumbrodie
    I am trying to solve a problem I have inherited with poor treatment of different data sources. I have a user table that contains BOTH good and evil users. create table `users`( `user_id` int(13) NOT NULL AUTO_INCREMENT , `email` varchar(255) , `name` varchar(255) , PRIMARY KEY (`user_id`) ); In this table the primary key is currently set to be user_id. I have another table ('users_evil') which contains ONLY the evil users (all the users from this table are included in the first table) - the user_id's on this table do NOT correspond to those in the first table. I want to have all my users in one table, and simply flag which are good and which are evil. What I want to do is alter the user table and add a column ('evil') which defaults to 0. I then want to dump the data from my 'users_evil') table and then run an INSERT..ON DUPLICATE KEY UPDATE with this data into the first table (setting 'evil'=1 where the emails match) The problem is that the 'PK' is set to the user_id and not the 'email'. Any suggestions, or even another strategy to successfully achive this. Can I run this statement but treat another column as PK only for the duration of the statement.

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  • Automatically create valid links

    - by Marcos Placona
    Hi, I'm new to python, so please bare with me :) I was wondering if there's any built-in way in python to append variables to URL's regardless of it's structure. I would like to have a URL variable (test=1) added to an URL which could have any of the following structures http://www.aaa.com (would simply add "/?test=1") to the end http://www.aaa.com/home (like the one above, would simply add "/?test=1") to the end http://www.aaa.com/?location=home (would figure out there's already a ? being used, and would add &test=1 to the end) http://www.aaa.com/?location=home&page=1 (like the one above, would figure out there's already a ? being used, and would add &test=1 to the end) I'd be happy to write domething to do it myself, but if python can already do it somehow, I'd me more than happy to use any built-in functionality that would save me some time ;-) Thanks in advance

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  • remote_form_for in index.html.erb file not working w/ AJAX...Ruby on Rails...

    - by bgadoci
    Just curious if I am overlooking something simple here. I have deployed the remote_form_for in the show.html.erb code before to render comments on a post (project in this case) without a problem. I have moved this code to the index view and seems to degrade to the normal form_for action (page refresh). I am not getting any javascript errors so not sure what is wrong here. Here is my code: index.html.erb <% remote_form_for [project, Comment.new] do |f| %> <p> <%= f.label :body, "New Comment" %><br/> <%= f.text_area (:body, :class => "textarea") %> </p> <p> <%= f.label :name, "Name" %> (Required)<br/> <%= f.text_field (:name, :class => "textfield") %> </p> <p> <%= f.label :email, "Email" %> (Required but will not be displayed)<br/> <%= f.text_field (:email, :class => "textfield") %> </p> <p><%= f.submit "Add Comment" %></p> <% end %> CommentsController#create def create @project = Project.find(params[:project_id]) @comment = @project.comments.create!(params[:comment]) respond_to do |format| format.html { redirect_to projects_path } format.js end end /views/comments/create.js.rjs page.insert_html :bottom, :commentwrapper, :partial => @comment page[@comment].visual_effect :highlight page[:new_comment].reset page.replace_html :notice, flash[:notice] flash.discard /views/comments/_comment.html.erb <% div_for comment do %> <div id="commentwrapper"> <% if admin? %> <%=link_to_remote "X", :url => [@project, comment], :method => :delete %> <% end %> <%= h(comment.body) %><br/><br/> Posted <%= time_ago_in_words(comment.created_at) %> ago by <%= h(comment.name) %> <% if admin? %> | <%= h(comment.email) %> <% end %></div> <% end %>

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  • Using before_create in Rails to normalize a many to many table

    - by weotch
    I am working on a pretty standard tagging implementation for a table of recipes. There is a many to many relationship between recipes and tags so the tags table will be normalized. Here are my models: class Recipe < ActiveRecord::Base has_many :tag_joins, :as => :parent has_many :tags, :through => :tag_joins end class TagJoin < ActiveRecord::Base belongs_to :parent, :polymorphic => true belongs_to :tag, :counter_cache => :usage_count end class Tag < ActiveRecord::Base has_many :tag_joins, :as => :parent has_many :recipes, :through => :tag_joins, :source => :parent , :source_type => 'Recipe' before_create :normalizeTable def normalizeTable t = Tag.find_by_name(self.name) if (t) j = TagJoin.new j.parent_type = self.tag_joins.parent_type j.parent_id = self.tag_joins.parent_id j.tag_id = t.id return false end end end The last bit, the before_create callback, is what I'm trying to get working. My goal is if there is an attempt to create a new tag with the same name as one already in the table, only a single row in the join table is produced, using the existing row in tags. Currently the code dies with: undefined method `parent_type' for #<Class:0x102f5ce38> Any suggestions?

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  • Multiple instance_of?

    - by c00lryguy
    How would I make Object#instance_of? accept multiple arguments so that something like the below example would work? class Foo; end class Bar; end class Baz; end my_foo = Foo.new my_bar = Bar.new my_baz = Baz.new my_foo.instance_of?(Foo, Bar) # => true my_bar.instance_of?(Foo, Bar) # => true my_baz.instance_of?(Foo, Bar) # => false

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  • 2-column table with two foreign keys. Performance/design question.

    - by Emanuel
    Hello everyone! I recently ran into a quite complex problem and after looking around a lot I couldn't find a solution to it. I've found answers to my questions many times before on stackoverflow.com, so I decided to post here. So I'm making a user/group managment system for a web-based project, and I'm storing all related data into a postgreSQL database. This system relies on three tables: USERS GROUPS GROUP_USERS The two first tables simply define all the users and all the groups on the site, and the last table, GROUP_USERS, stores the groups every user is part of. It only has two columns: USER_ID GROUP_ID Since every user can be a member of several groups, I decided to make a separate table for this purpose, rather than storing a comma separated column in the USERS-table. Now, both columns are foreign keys, and I want to make them both primary keys as well, this since each combination of USER_ID and GROUP_ID has to be unique, and if I give them the constraint UNIQUE pgAdmin tells me that each table should have at least one Primary key. But now I am stuck with what seems to be a lot of indexes and relations to a very small table only containing numbers. In the end, I want this table to be as fast as possible, even if containing tens of thousands of rows. Size on disk shouldn't be a problem since its just all numbers anyway, but it feels quite stupid to have a full-sized index refering to a smaller table. Should I stick with my current solution, store comma-separated values in a column in the USERS-table or is there any other solution I should be aware of. PS. I don't want to use an array-column, even if they are supported by postgreSQL. I want to be as generic as possible so I can switch database later on, if necessary. EDIT: I other words, will using a compound primary key and two foreign keys in one table with only two columns have a negative impact on performance rather than the opposite due to the size of the generated index? Thank you!

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  • convert Ruby to C languge

    - by alaamh
    I have seen this sample written in Ruby code, how i can simulate it in C language? Open3.popen3(command) do |stdin, stdout, stderr| @stop_stdin = stdin while !stdout.eof do output = stdout.read(1024 * 100) list_pipes.each do |out| out.print output end end end

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