Search Results

Search found 62355 results on 2495 pages for 'data collection'.

Page 162/2495 | < Previous Page | 158 159 160 161 162 163 164 165 166 167 168 169  | Next Page >

  • content_tag_for a collection in Rails?

    - by Nick
    I have a Post model. Posts have many Comments. I want to generate a <ul> element for post.comments using content_tag_for. Ideally, it'd produce <ul id="comments_post_7" class="comments"> ... </ul> where 7 is the ID of the Post. The closest I can get uses <% content-tag-for :ul post, :comments do %> which produces <ul id="comments_post_7" class="post"> ... </ul> which is pretty close, except for the class="post". Using :class => :comments in the content_tag_for yields class="post comments", but I just want class="comments". It seems logical that I'd be able to use something like <% content_tag_for :ul post.comments do %> but, sadly, that yields <ul id="array_2181653100" class="array"> ... </ul> I've searched far and wide. I feel like I'm missing some elegant way to do this. Am I? Because, seriously, <ul id="comments_post_<%= post.id %>" class="comments"> is painful.

    Read the article

  • Best practice to avoid InvalidOperationException: Collection was modified?

    - by Roflcoptr
    Very often I need something like that: foreach (Line line in lines) { if (line.FullfilsCertainConditions()) { lines.Remove(line) } } This does not work, because I always get a InvalidOperationException because the Enumerator was changed during the loop. So I changed all my loops of this kind to the following: List<Line> remove = new List<Line>(); foreach (Line line in lines) { if (line.FullfilsCertainConditions()) { remove.Add(line) } } foreach (Line line in remove) { { lines.Remove(line); } I'm not sure if this is really the best way since in the worst case I have to iterate 2 times over the original list and so it needs time 2n instead of n. Is there a better way to do this?

    Read the article

  • C# What would happen to GC if I run process with priority = RealTime?

    - by Bobb
    I have a C# app which runs with priority RealTime. It was all fine until I made few hectic changes in past 2 days. Now it runs out of memory in few hours. I am trying to find whether it is a memory leak I created of this is because I consume lot more objects than before and GC simply cant collect them because it runs with same priority. My question is - what could happen to GC when it tries to collect objects in application with RealTime priority (there is also at least one thread running with Highest thread priority)? (P.S. by realtime priority I mean Process.GetCurrentProcess().PriorityClass = ProcessPriorityClass.RealTime)

    Read the article

  • Java GC: top object classes promoted (by size)?

    - by Java Geek
    Hello! Please let me know what is the best way to determine composition of young generation memory promoted to old generation, after each young GC event? Ideally I would like to know class names which are responsible say, for 80% of heap in each "young gen - old gen" promotion chunk; Example: I have 600M young gen, each tenure promotes 6M; I want to know which objects compose this 6M. Thank you.

    Read the article

  • Binding a select box to a Collection (with Spring)

    - by WiPU
    i have the following problem. I have a form bean and in this bean is a list with objects. List<SomeObjectForm> toDisplay; Now i want map a html select to this list. Something like that: <form:select id="inputGroupFields" path="templateKey" multiple="true"... <form:select id="inputGroupFields" path="templateKey.id" multiple="true"... And this dosnt work of course. Now i have tryed to add different custom Converter like: myConv implements Converter<SomeObjectForm, String> myConv extends StringToObject And this also not work. I'm not sure if this is the right approach or there is a easier way to do that. Some addional Infos: --i'm using spring 3.0.5 --all this happens during a web flow regards and thanks, WiPu

    Read the article

  • How to store and collect data for mining such information as most viewed for last 24 hours, last 7 d

    - by Kirzilla
    Hello, Let's imagine that we have high traffic project (a tube site) which should provide sorting using this options (NOT IN REAL TIME). Number of videos is about 200K and all information about videos is stored in MySQL. Number of daily video views is about 1.5KK. As instruments we have Hard Disk Drive (text files), MySQL, Redis. Views top viewed top viewed last 24 hours top viewed last 7 days top viewed last 30 days top rated last 365 days How should I store such information? The first idea is to log all visits to text files (single file per hour, for example visits_20080101_00.log). At the beginning of each hour calculate views per video for previous hour and insert this information into MySQL. Then recalculate totals (for last 24 hours) and update statistics in tables. At the beginning of every day we have to do the same but recalculate for last 7 days, last 30 days, last 365 days. This method seems to be very poor for me because we have to store information about last 365 days for each video to make correct calculations. Is there any other good methods? Probably, we have to choose another instruments for this? Thank you.

    Read the article

  • How to write a value validation method for core data?

    - by mystify
    The docs say: you should implement methods of the form validate:error:, as defined by the NSKeyValueCoding protocol so lets say I have an attribute which is an int: friendAge I want to make sure that any friend may not be younger than 30. So how would I make that validation method? -validateFriendAge:error: What am I gonna do in there, exactly? And what shall I do with that NSError I get passed? I think it has an dictionary where I can return a humanly readable string in an arbitrary language (i.e. the one that's used currently), so I can output a reasonable error like: "Friend is not old enough"... how to do that?

    Read the article

  • How do I ensure data consistency in this concurrent situation?

    - by MalcomTucker
    The problem is this: I have multiple competing threads (100+) that need to access one database table Each thread will pass a String name - where that name exists in the table, the database should return the id for the row, where the name doesn't already exist, the name should be inserted and the id returned. There can only ever be one instance of name in the database - ie. name must be unique How do I ensure that thread one doesn't insert name1 at the same time as thread two also tries to insert name1? In other words, how do I guarantee the uniqueness of name in a concurrent environment? This also needs to be as efficient as possible - this has the potential to be a serious bottleneck. I am using MySQL and Java. Thanks

    Read the article

  • Rspec and Rails 3 - Problem Validating Nested Attribute Collection Size

    - by MunkiPhD
    When I create my Rspec tests, I keep getting a validation of false as opposed to true for the following tests. I've tried everything and the following is the measly code that I have now - so if it's waaaaay wrong, that's why. class Master < ActiveRecord::Base attr_accessible :name, :specific_size # Associations ---------------------- has_many :line_items accepts_nested_attributes_for :line_items, :allow_destroy => true, :reject_if => lambda { |a| a[:item_id].blank? } # Validations ----------------------- validates :name, :presence => true, :length => {:minimum => 3, :maximum => 30} validates :specific_size, :presence => true, :length => {:minimum => 4, :maximum => 30} validate :verify_items_count def verify_items_count if self.line_items.size < 2 errors.add(:base, "Not enough items to create a master") end end end And here it the items model: class LineItem < ActiveRecord::Base attr_accessible :specific_size, :other_item_type_id # Validations -------------------- validates :other_item_type_id, :presence => true validates :master_id, :presence => true validates :specific_size, :presence => true # Associations --------------------- belongs_to :other_item_type belongs_to :master end The RSpec Tests: before(:each) do @master_lines = [] @master_lines << LineItem.new(:other_item_type_id => 1, :master_id => 2, :specific_size => 1) @master_lines << LineItem.new(:other_item_type_id => 2, :master_id => 2, :specific_size => 1) @attr = {:name => "Some Master", :specific_size => "1 giga"} end it "should create a new instance given a valid name and specific size" do @master = Master.create(@attr) line_item_one = @master.line_items.build(:other_item_type_id => 1, :specific_size => 1) line_item_two = @master.line_items.build(:other_item_type_id => 2, :specific_size => 2) @master.line_items.size === 2 @master.should be_valid end it "should have at least two items to be valid" do master = Master.new(:name => "test name", :specific_size => "1 mega") master_item_one = LineItem.new(:other_item_type_id => 1, :specific_size => 2) master_item_two = LineItem.new(:other_item_type_id => 2, :specific_size => 1) master.line_items << master_item_one master.should_not be_valid master.line_items << master_item_two master.line_items.size.should === 2 master.should be_valid end I'm very new to Rspec and Rails - and I've been failing at this for the past couple of hours. Thanks for any help in advance.

    Read the article

  • Accessing child collection in query

    - by Gokul
    I am populating a list using List<Country> countries = new List<Country> { new Country() { CountryID = "US", City = new List<City> { new City() { CountryID = "US", CityName="dfdsf", sqkm = 2803 } } }; and so on How to access sqkm in the following query? var countryQuery = countries .Select(c => new { Id = c.CountryId, Area = c.City.sqkm???}); c.city.sqkm gives compilation error...how to modify query

    Read the article

  • What's does "cardinality of an relationship" mean in Core Data?

    - by dontWatchMyProfile
    From the docs: If all of a managed object's relationship delete rules are Nullify, then for that object at least there is no additional work to do (you may have to consider other objects that were at the destination of the relationship—if the inverse relationship was either mandatory or had a lower limit on cardinality, then the destination object or objects might be in an invalid state). Does someone have an example of this cardinality thing? What's this good for and what's important to know about this? (sounds very important...)

    Read the article

  • Searching for online database software/cms

    - by ButterdBread
    I am searching for a software or CMS that manages and displays large online databases, as some kind of frontend to MySQL or any other database. It should be accessible through the browser, be as secure as possible (offering login). The data I'd like to store would be personal information such as name, adress and birthday - also I'd need to be able to add custom fields as well. Also forms and the possibility to download the data in an excel? table would be great. PHPmyadmin is not an option, it should be similar to a CRM but more closely adapted to managing database tables, searching for entries and filtering data. It should be possible to have many user accounts with different rights, with each of them being able to acces certain parts of the data and entering own data. Is there something out there, that might get close to what I imagine? I appreciate any help!

    Read the article

  • Is it compulsory to learn about Data Structures if you want to be a Java/C++ programmer ?

    - by happysoul
    So do I like really need to learn about them ? Isn't there an interesting way to learn about stacks, linked lists, heaps ,etc ? I found it a boring subject. **While posting this question it showed some warning.Am I not allowed to post such a question ? Admins please clarify and I will delete it :/ Warning :: The question you're asking appears subjective and is likely to be closed.

    Read the article

  • Render different view depending on the type of the data

    - by Miau
    Hi there So lets suppose we have an action in a controller that looks a bit like this: public ViewResult SomeAction(int id) { var data = _someService.GetData(id); ... //create new view model based on the data here return View(viewModel); } What I m trying to figure out is the best way to render a diferent view based on the type fo the data. the "_someService.GetData method returns an data that knows its out type (ie not only you can do typeof(data) but also you can do data.DataType and you ll get an enum value so I could achieve what I m trying to do doing something kinda like this public ViewResult SomeAction(int id) { var data = _someService.GetData(id); //I m mapping fields to the viewModel here var viewModel = GetViewModel(data); swtich(data.DataType) case DataType.TypeOne: return View("TypeOne", viewModel); break; ... } But this does not seem to be the nicest way, (I dont event know if it would work) Is this the way to go? Should I use some sort of RenderPartial Aproach? after all , waht will change in the view is mostly the order of the data (ie the rest of the view would be quite similar) Cheers

    Read the article

  • Large memory chunk not garbage collected

    - by Niels
    In a hunt for a memory-leak in my app I chased down a behaviour I can't understand. I allocate a large memory block, but it doesn't get garbage-collected resulting in a OOM, unless I explicit null the reference in onDestroy. In this example I have two almost identical activities that switch between each others. Both have a single button. On pressing the button MainActivity starts OOMActivity and OOMActivity returns by calling finish(). After pressing the buttons a few times, Android throws a OOMException. If i add the the onDestroy to OOMActivity and explicit null the reference to the memory chunk, I can see in the log that the memory is correctly freed. Why doesn't the memory get freed automatically without the nulling? MainActivity: package com.example.oom; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; public class MainActivity extends Activity implements OnClickListener { private int buttonId; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); System.gc(); Button OOMButton = new Button(this); OOMButton.setText("OOM"); buttonId = OOMButton.getId(); setContentView(OOMButton); OOMButton.setOnClickListener(this); } @Override public void onClick(View v) { if (v.getId() == buttonId) { Intent leakIntent = new Intent(this, OOMActivity.class); startActivity(leakIntent); } } } OOMActivity: public class OOMActivity extends Activity implements OnClickListener { private static final int WASTE_SIZE = 20000000; private byte[] waste; private int buttonId; protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Button BackButton = new Button(this); BackButton.setText("Back"); buttonId = BackButton.getId(); setContentView(BackButton); BackButton.setOnClickListener(this); waste = new byte[WASTE_SIZE]; } public void onClick(View view) { if (view.getId() == buttonId) { finish(); } } }

    Read the article

  • Adding Timestamp to Java's GC messages in Tomcat 6

    - by ripper234
    I turned on Java's GC log options -XX:+PrintGC -XX:+PrintGCTimeStamps -XX:+PrintGCDetails Which print out these messages to standard output (catalina.out): 314.884: [CMS-concurrent-mark-start] 315.014: [CMS-concurrent-mark: 0.129/0.129 secs] [Times: user=0.14 sys=0.00, real=0.13 secs] 315.014: [CMS-concurrent-preclean-start] 315.016: [CMS-concurrent-preclean: 0.003/0.003 secs] [Times: user=0.00 sys=0.00, real=0.00 secs] 315.016: [CMS-concurrent-abortable-preclean-start] 332.055: [GC 332.055: [ParNew: 17128K->84K(19136K), 0.0017700 secs] 88000K->70956K(522176K) icms_dc=4 , 0.0018660 secs] [Times: user=0.00 sys=0.00, real=0.00 secs] CMS: abort preclean due to time 352.253: [CMS-concurrent-abortable-preclean: 0.023/37.237 secs] [Times: user=0.78 sys=0.02, real=37.23 secs] How can I make these log lines appear with an actual timestamp (including date) instead of these numbers, which presumably mean "time since JVM started" ?

    Read the article

  • How to apply a function to a collection of elements

    - by Cue
    Consider I have an array of elements out of which I want to create a new 'iterable' which on every next applies a custom 'transformation'. What's the proper way of doing it under python 2.x? For people familiar with Java, the equivalent is Iterables#transform from google's collections framework.

    Read the article

  • linq subquery child collection to string

    - by bill
    Hi All, i am trying to figure out how to write a linq query that will return a child collections "name" property as a string. I have a BO that has a "options" property where the options are the "name" property of each option in an "order" object. I would like the result to look something like order.id = 12312 order.date = 12/03/10 order.options = "Option 1 Name, Option 2 Name, Option 3 Name" I hope this makes sense. thanks for any and all help!

    Read the article

  • How to easily apply a function to a collection in C++

    - by Jesse Beder
    I'm storing images as arrays, templated based on the type of their elements, like Image<unsigned> or Image<float>, etc. Frequently, I need to perform operations on these images; for example, I might need to add two images, or square an image (elementwise), and so on. All of the operations are elementwise. I'd like get as close as possible to writing things like: float Add(float a, float b) { return a+b; } Image<float> result = Add(img1, img2); and even better, things like complex ComplexCombine(float a, float b) { return complex(a, b); } Image<complex> result = ComplexCombine(img1, img2); or struct FindMax { unsigned currentMax; FindMax(): currentMax(0) {} void operator(unsigned a) { if(a > currentMax) currentMax = a; } }; FindMax findMax; findMax(img); findMax.currentMax; // now contains the maximum value of 'img' Now, I obviously can't exactly do that; I've written something so that I can call: Image<float> result = Apply(img1, img2, Add); but I can't seem to figure out a generic way for it to detect the return type of the function/function object passed, so my ComplexCombine example above is out; also, I have to write a new one for each number of arguments I'd like to pass (which seems inevitable). Any thoughts on how to achieve this (with as little boilerplate code as possible)?

    Read the article

  • Peculiar JRE behaviour running RMI server under load, should I worry?

    - by darri
    I've been developing a minimalistic Java rich client CRUD application framework for the past few years, mostly as a hobby but also actively using it to write applications for my current employer. The framework provides database access to clients either via a local JDBC based connection or a lightweight RMI server. Last night I started a load testing application, which ran 100 headless clients, bombarding the server with requests, each client waiting only 1 - 2 seconds between running simple use cases, consisting of selecting records along with associated detail records from a simple e-store database (Chinook). This morning when I looked at the telemetry results from the server profiling session I noticed something which to me seemed strange (and made me keep the setup running for the remainder of the day), I don't really know what conclusions to draw from it. Here are the results: Memory GC activity Threads CPU load Interesting, right? So the question is, is this normal or erratic? Is this simply the JRE (1.6.0_03 on Windows XP) doing it's thing (perhaps related to the JRE configuration) or is my framework design somehow causing this? Running the server against MySQL as opposed to an embedded H2 database does not affect the pattern. I am leaving out the details of my server design, but I'll be happy to elaborate if this behaviour is deemed erratic.

    Read the article

< Previous Page | 158 159 160 161 162 163 164 165 166 167 168 169  | Next Page >