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  • Error: "an object reference is required for the non-static field, method or property..."

    - by user300484
    Hi! Im creating an application on C#. Its function is to evualuate if a given is prime and if the same swapped number is prime as well. When I build my solution on Visual Studio, it says that "an object reference is required for the non-static field, method or property...". Im having this problem with the "volteado" and "siprimo" methods. Can you tell me where is the problem and how i can fix it? thank you! namespace ConsoleApplication1 { class Program { static void Main(string[] args) { Console.Write("Write a number: "); long a= Convert.ToInt64(Console.ReadLine()); // a is the number given by the user long av = volteado(a); // av is "a" but swapped if (siprimo(a) == false && siprimo(av) == false) Console.WriteLine("Both original and swapped numbers are prime."); else Console.WriteLine("One of the numbers isnt prime."); Console.ReadLine(); } private bool siprimo(long a) {// evaluate if the received number is prime bool sp = true; for (long k = 2; k <= a / 2; k++) if (a % k == 0) sp = false; return sp; } private long volteado(long a) {// swap the received number long v = 0; while (a > 0) { v = 10 * v + a % 10; a /= 10; } return v; } } }

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  • Why is this linq extension method hit the database twice?

    - by Pure.Krome
    Hi folks, I have an extension method called ToListIfNotNullOrEmpty(), which is hitting the DB twice, instead of once. The first time it returns one result, the second time it returns all the correct results. I'm pretty sure the first time it hits the database, is when the .Any() method is getting called. here's the code. public static IList<T> ToListIfNotNullOrEmpty<T>(this IEnumerable<T> value) { if (value.IsNullOrEmpty()) { return null; } if (value is IList<T>) { return (value as IList<T>); } return new List<T>(value); } public static bool IsNullOrEmpty<T>(this IEnumerable<T> value) { if (value != null) { return !value.Any(); } return true; } I'm hoping to refactor it so that, before the .Any() method is called, it actually enumerates through the entire list. If i do the following, only one DB call is made, because the list is already enumerated. var pewPew = (from x in whatever select x) .ToList() // This enumerates. .ToListIsNotNullOrEmpty(); // This checks the enumerated result. I sorta don't really want to call ToList() then my extension method. Any ideas, folks?

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  • What is the difference between a restful route method for getting an index vs. creating a new object

    - by Jason
    According to rake routes, there's the same path for getting an index of objects as there is for creating a new object: cars GET /cars(.:format) {:controller=>"plugs", :what=>"car", :action=>"index"} POST /cars(.:format) {:controller=>"plugs", :what=>"car", :action=>"create"} Obviously, the HTTP verb is what distinguishes between them. I want the "create" version of the cars_path method, not the "index" version. My question is what route method do you invoke to choose the one you want? I'm telling cucumber what path to generate with this: when /the car plug preview page for "(.+)"/ cars_path(:action => :create, :method => :post) ...but it always chooses the "index" action, not "create". I've tried lots of combinations for the hash argument following cars_path and nothing changes it from choosing "index" instead of "create". I'll get an error like this: cars_url failed to generate from {:controller=>"plugs", :method=>:post, :what=>"car", :action=>"create"}, expected: {:controller=>"plugs", :what=>"car", :action=>"index"}, diff: {:method=>:post, :action=>"index"} (ActionController::RoutingError) This seems like a very simple question but I've had no luck googling for it, so could use some advice. Thanks.

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  • Conditional insert as a single database transaction in HSQLDB 1.8?

    - by Kevin Pauli
    I'm using a particular database table like a "Set" data structure, i.e., you can attempt to insert the same row several times, but it will only contain one instance. The primary key is a natural key. For example, I want the following series of operations to work fine, and result in only one row for Oklahoma: insert into states_visited (state_name) values ('Oklahoma'); insert into states_visited (state_name) values ('Texas'); insert into states_visited (state_name) values ('Oklahoma'); I am of course getting an error due to the duplicate primary key on subsequent inserts of the same value. Is there a way to make the insert conditional, so that these errors are not thrown? I.e. only do the the insert if the natural key does not already exist? I know I could do a where clause and a subquery to test for the row's existence first, but it seems that would be expensive. That's 2 physical operations for one logical "conditional insert" operation. Anything like this in SQL? FYI I am using HSQLDB 1.8

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  • How to get address the object of an related entity with CoreData ?

    - by eemceebee
    Hi Ok, after I ran into a dead end modifieing an existing Apple example for CoreData, I started completely new creating my own project and that worked fine,..... until I tried to access a related entity. So here is what I did. I created 2 entities, where one is just the detail information of the other one, so there is a one-2-one relationship. Entity #1, Stocks: name value details -- relationship to Entity #2 Entity #2, StockDetails: bank published stock -- relationship to Entity #1 Now, I created the "Managed Object Class" for both of the Entities. Then I created a few lines to put some data into it NSManagedObjectContext *context = [self managedObjectContext]; Stocks *stockinfo= [NSEntityDescription insertNewObjectForEntityForName:@"Stocks" inManagedObjectContext:context]; stockinfo.name = @"Apple"; stockinfo.value = [NSNumber numberWithInt:200]; StockDetails *thestockdetails = [NSEntityDescription insertNewObjectForEntityForName:@"StockDetails" inManagedObjectContext:context]; thestockdetails.bank = @"Bank of America"; thestockdetails.published = [NSDate date]; thestockdetails.stock = stocks_; stockinfo.details = thestockdetails ; NSError *error; if (![context save:&error]) { NSLog(@"A Problem occured, couldn't save: %@", [error localizedDescription]); } Just want to mention here, that I do not get an error with this. Next I put everything into a UITableViewController for a preview and another for a detail view. The preview just shows infos form Entity #1 (Stocks) and when selected it shows the detail view. Now here I also display the infos form Entity #1 (Stocks) but I want to show the Entity #2 (StockDetails) aswell. This is how I try to access the data : StockDetails *details_ = [stockinfo details]; And this gives me a EXC_BAD_ACCESS. So any idea what I am doing wrong here ? Thanks

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  • Is it possible, in a django template, to check if an object is contained in a list

    - by AlexH
    I'm very new to django, about a week into it. I'm making a site where users enter stuff, then other users can vote on whether they like the stuff or not. I know it's not so novel, but it's a good project to learn a bunch of tools. I have a many-to-many table for storing who likes or dislikes what. Before I render the page, I pull out all the likes and dislikes for the current user, along with the stuff I'm going to show on the page. When I render the page, I go through the list of stuff I'm going to show and print them out one at a time. I want to show the user which stuff they liked, and which they didn't. So in my django template, I have an object called entry. I also have two lists of objects called likes and dislikes. Is there any way to determine if entry is a member of either list, inside my django template. I think what I'm looking for is a filter where I can say something like {% if entry|in:likes %} or {% if likes|contains:entry %} I know I could add a method to my model and check for each entry individually, but that seems like it would be database intensive. Is there a better way to think about this problem?

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  • LINQ .Cast() extension method fails but (type)object works.

    - by Ben Robinson
    To convert between some LINQ to SQL objects and DTOs we have created explicit cast operators on the DTOs. That way we can do the following: DTOType MyDTO = (LinqToSQLType)MyLinq2SQLObj; This works well. However when you try to cast using the LINQ .Cast() extension method it trows an invalid cast exception saying cannot cast type Linq2SQLType to type DTOType. i.e. the below does not work List<DTO.Name> Names = dbContact.tNames.Cast<DTO.Name>() .ToList(); But the below works fine: DAL.tName MyDalName = new DAL.tName(); DTO.Name MyDTOName = (DTO.Name)MyDalName; and the below also works fine List<DTO.Name> Names = dbContact.tNames.Select(name => (DTO.Name)name) .ToList(); Why does the .Cast() extension method throw an invalid cast exception? I have used the .Cast() extension method in this way many times in the past and when you are casting something like a base type to a derived type it works fine, but falls over when the object has an explicit cast operator.

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  • Trying to grab several random videos from database, but it just shows the same one all the time.

    - by Birk
    Hi guys, I'm trying to grab several random videos from my database, and have them show on a page. However, it just keeps on grabbing the same video rather than several different ones. So I end up with 5 of the same video rather than 5 different ones. Here's the grab random PHP code file... and after it is the template output file. //===================================================== // Random | Previous | Next //===================================================== $show['random'] = $db->quick_fetch( "SELECT file_id, title, title_seo, category_id, thumb FROM files WHERE files.category_id = '".$show['main']['category_id']."' AND files.verified=1 ORDER BY RAND() LIMIT 0,1; "); Here's the template CSS html thingy code I have this pasted 5 times to show 5 random videos <td valign="top" width="53%"><? $sql="select * from files ORDER BY rand() limit 0,5"; $res=@mysql_query($sql); $data=@mysql_result($res,0,'filename'); $id=@mysql_result($res,0,'file_id'); $title=@mysql_result($res,0,'title'); $title2=str_replace(" ", "-",$title); $path="{$siteurl}/media/{$file.random.file_id}/{$file.random.title_seo}/"; $img="{$siteurl}/thumbs/{$file.random.thumb}"; echo " {$file.random.title}"

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  • Is it okay for multiple objects to retain the same object in Objective-C/Cocoa?

    - by Andrew Arrow
    Say I have a tableview class that lists 100 Foo objects. It has: @property (nonatomic, retain) NSMutableArray* fooList; and I fill it up with Foos like: self.fooList = [NSMutableArray array]; while (something) { Foo* foo = [[Foo alloc] init]; [fooList addObject:foo]; [foo release]; } First question: because the NSMutableArray is marked as retain, that means all the objects inside it are retained too? Am I correctly adding the foo and releasing the local copy after it's been added to the array? Or am I missing a retain call? Then if the user selects one specific row in the table and I want to display a detail Foo view I call: FooView* localView = [[FooView alloc] initWithFoo:[self.fooList objectAtIndex:indexPath.row]]; [self.navigationController pushViewController:localView animated:YES]; [localView release]; Now the FooView class has: @property (nonatomic, retain) Foo* theFoo; so now BOTH the array is holding on to that Foo as well as the FooView. But that seems okay right? When the user hits the back button dealloc will be called on FooView and [theFoo release] will be called. Then another back button is hit and dealloc is called on the tableview class and [fooList release] is called. You might argue that the FooView class should have: @property (nonatomic, assign) Foo* theFoo; vs. retain. But sometimes the FooView class is called with a Foo that's not also in an array. So I wanted to make sure it was okay to have two objects holding on to the same other object.

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  • Is there a more memory efficient way to search through a Core Data database?

    - by Kristian K
    I need to see if an object that I have obtained from a CSV file with a unique identifier exists in my Core Data Database, and this is the code I deemed suitable for this task: NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity; entity = [NSEntityDescription entityForName:@"ICD9" inManagedObjectContext:passedContext]; [fetchRequest setEntity:entity]; NSPredicate *pred = [NSPredicate predicateWithFormat:@"uniqueID like %@", uniqueIdentifier]; [fetchRequest setPredicate:pred]; NSError *err; NSArray* icd9s = [passedContext executeFetchRequest:fetchRequest error:&err]; [fetchRequest release]; if ([icd9s count] > 0) { for (int i = 0; i < [icd9s count]; i++) { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc]init]; NSString *name = [[icd9s objectAtIndex:i] valueForKey:@"uniqueID"]; if ([name caseInsensitiveCompare:uniqueIdentifier] == NSOrderedSame && name != nil) { [pool release]; return [icd9s objectAtIndex:i]; } [pool release]; } } return nil; After more thorough testing it appears that this code is responsible for a huge amount of leaking in the app I'm writing (it crashes on a 3GS before making it 20 percent through the 1459 items). I feel like this isn't the most efficient way to do this, any suggestions for a more memory efficient way? Thanks in advance!

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  • Why don't I need to bind my vertex buffer object before calling glDrawArrays?

    - by valmo
    I'm a bit confused why this still renders. I thought you need to bind a vertex buffer object so that glDrawArrays knows which vertex buffer to use. Here is my initialisation code.. // Create and bind vertex array to store vertex attribute states. glGenVertexArraysOES(NUM_VERTEX_ARRAYS, &m_vertexArray); glBindVertexArrayOES(m_vertexArray); // Create and bind vertex buffer to store vertex data. glGenBuffers(NUM_VERTEX_BUFFERS, &m_vertexBuffer); glBindBuffer(GL_ARRAY_BUFFER, m_vertexBuffer); glBufferData(GL_ARRAY_BUFFER, sizeof(Vertex) * 36, &m_vertices[0], GL_STATIC_DRAW); glEnableVertexAttribArray(VertexAttribPosition); glVertexAttribPointer(VertexAttribPosition, 3, GL_FLOAT, GL_FALSE, 24, BUFFER_OFFSET(0)); glEnableVertexAttribArray(VertexAttribNormal); glVertexAttribPointer(VertexAttribNormal, 3, GL_FLOAT, GL_FALSE, 24, BUFFER_OFFSET(12)); glBindBuffer(GL_ARRAY_BUFFER, 0); glBindVertexArrayOES(0); Here is my render code. I'm confused why glDrawArrays still works when I bind 0 to GL_ARRAY_BUFFER. glBindVertexArrayOES(m_vertexArray); glBindBuffer(GL_ARRAY_BUFFER, 0); glDrawArrays(GL_TRIANGLES, 0, 36); glBindVertexArrayOES(0);

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  • Sql Server 2005 Database Tables - Row Comparison Column By Column.

    - by Goober
    Scenario I have an TWO datbase tables of exactly the SAME STRUCTURE. The difference between these tables is that one contains data populated by one application and the other is populated by a different application. Each application is trying to produce the same result, but using two different methods of implementation. Proposed Idea What I want to do, is run both applications, which will roughly produce 35000 rows containing 10 columns each - So all in all, 70000 rows of data, I then want to compare each row of data, COLUMN BY COLUMN to check whether the values are the same or not. Current Thoughts Since there is so much data to compare, I feel that the best way in which to do this would be to write an application, preferably in C# (but if necessary, T-sql), to compare each row of data column by column, and write out any failed comparisons to a text log file. Question Could anybody suggest an efficient way in which to perform column by column row comparison for 70000 rows worth of data? I'm struggling for ideas on how to tackle this problem. Extra Detail The two applications are both written in C# .Net 3.5. The Database is running on Sql Server 2005. Help greatly appreciated.

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  • why does this knockout method receive a form element instead of the object its nested in?

    - by ladookie
    I have this HTML: <ul class="chat_list" data-bind="foreach: chats"> <li> <div class="chat_response" data-bind="visible: CommentList().length == 0"> <form data-bind="submit: $root.addComment"> <input class="comment_field" placeholder="Comment…" data-bind="value: NewCommentText" /> </form> </div> </li> </ul> and this JavaScript: function ChatListViewModel(chats) { // var self = this; self.chats = ko.observableArray(ko.utils.arrayMap(chats, function (chat) { return { CourseItemDescription: chat.CourseItemDescription, CommentList: ko.observableArray(chat.CommentList), CourseItemID: chat.CourseItemID, UserName: chat.UserName, ChatGroupNumber: chat.ChatGroupNumber, ChatCount: chat.ChatCount, NewCommentText: ko.observable("") }; })); self.newChatText = ko.observable(); self.addComment = function (chat) { var newComment = { CourseItemDescription: chat.NewCommentText(), ParentCourseItemID: chat.CourseItemID, CourseID: $.CourseLogic.dataitem.CourseID, AccountID: $.CourseLogic.dataitem.AccountID, SystemObjectID: $.CourseLogic.dataitem.CommentSystemObjectID, SystemObjectName: "Comments", UserName: chat.UserName }; chat.CommentList.push(newComment); chat.NewCommentText(""); }; } ko.applyBindings(new ChatListViewModel(initialData)); When I go into the debugger it shows that the chat parameter of the addComment() function is a form element instead of a chat object. Why is this happening?

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  • Why does JavaScript's getElementsByClassName provide an object that is NOT an array?

    - by Paragon
    I'm trying to get a list in JavaScript (not using jQuery) of all the elements on the page with a specific class name. I therefore employ the getElementsByClassName() function as follows: var expand_buttons = document.getElementsByClassName('expand'); console.log(expand_buttons, expand_buttons.length, expand_buttons[0]); Note that I have three anchor elements on my page with the class 'expand'. This console.log() outputs [] 0 undefined Next, for kicks, I threw expand_buttons into its own array as follows: var newArray = new Array(expand_buttons); console.log(newArray, newArray.length); This suddenly outputs [NodeList[3]] 1 and I can click through the nodelist and see the attributes of the three 'expand' anchor elements on the page. It's also worth noting that I was able to get my code working in a w3schools test page. It may also be of note that my use of document.getElementsByName actually does output (to the console) an array of elements, but when I ask for its length, it tells me 0. Similarly, if I try to access an array element using array_name[0] as normal, it outputs 'undefined', despite there clearly being an element inside of an array when I print the object to the console. Does anybody have any idea why this might be? I just want to loop through DOM elements, and I'm avoiding jQuery at the moment because I'm trying to practice coding with vanilla JavaScript. Thanks, ParagonRG

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  • Using TXMLDocument to serialize form settings to XML and database.

    - by LukLed
    I have an interface: type IXMLSerializable = interface function SaveToXML : DOMString; function SaveToXMLDocument : IXMLDocument; procedure LoadFromXML(AXML : DOMString); end; It is used to serialize some settings of forms or frames to xml. Simple implementation: SaveToXMLDocument: function TSomething.SaveToXMLDocument: IXMLDocument; begin Result := TXMLDocument.Create(nil); with Result do begin Active := True; with AddChild(Self.Name) do begin AddChild(edSomeTextBox.Name).Attributes['Text'] := edSomeTextBox.Text; end; end; Result := XMLDoc; end; LoadFromXML: procedure TSomething.LoadFromXML(AXML: DOMString); var XMLDoc : IXMLDocument; I : Integer; begin XMLDoc := TXMLDocument.Create(nil); with XMLDoc do begin LoadFromXML(AXML); Active := True; with ChildNodes[0] do begin for I := 0 to ChildNodes.Count-1 do begin If ChildNodes[I].NodeName = 'edSomeTextBox' then edSomeTextBox.Text := ChildNodes[I].Attributes['Text']; end; end; end; end; SaveToXML: function TSomething.SaveToXML: DOMString; begin SaveToXMLDocument.SaveToXML(Result); end; DOMString result of SaveToXML is saved to database to blob field. I had some encoding issues with other implementations and this one works fine (right now). Do you see any dangers in this code? Can I have issues with different settings on various machines and systems?

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  • What collection object is appropriate for fixed ordering of values?

    - by makerofthings7
    Scenario: I am tracking several performance counters and have a CounterDescription[] correlate to DataSnapshot[]... where CounterDescription[n] describes the data loaded within DataSnapshot[n]. I want to expose an easy to use API within C# that will allow for the easy and efficient expansion of the arrays. For example CounterDescription[0] = Humidity; DataSnapshot[0] = .9; CounterDescription[1] = Temp; DataSnapshot[1] = 63; My upload object is defined like this: Note how my intent is to correlate many Datasnapshots with a dattime reference, and using the offset of the data to refer to its meaning. This was determined to be the most efficient way to store the data on the back-end, and has now reflected itself into the following structure: public class myDataObject { [DataMember] public SortedDictionary<DateTime, float[]> Pages { get; set; } /// <summary> /// An array that identifies what each position in the array is supposed to be /// </summary> [DataMember] public CounterDescription[] Counters { get; set; } } I will need to expand each of these arrays (float[] and CounterDescription[] ), but whatever data already exists must stay in that relative offset. Which .NET objects support this? I think Array[] , LinkedList<t>, and List<t> Are able to keep the data fixed in the right locations. What do you think?

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  • How can i pull an image and data from a Database?

    - by user1851377
    I am trying to pull data from a Database using C#.net and use a Foreach loop to make it visible on a page. Every time i run the code i only get one item that shows up when i know that there is at least 7 items in the DB. i have placed the code below for the C#. SqlConnection oConnection = new SqlConnection(ConfigurationManager.ConnectionStrings["HomeGrownEnergyConnectionString"].ToString()); string sqlEnergy = "Select * from Product p where p.ProductTypeId=3"; SqlCommand oCmd = new SqlCommand(sqlEnergy, oConnection); DataTable dtenergy = new DataTable(); SqlDataAdapter oDa = new SqlDataAdapter(oCmd); try { oConnection.Open(); ; oDa.Fill(dtenergy); } catch (Exception ex) { lblnodata.Text = ex.Message; return; } finally { oConnection.Close(); } DataTableReader results = dtenergy.CreateDataReader(); if (results.HasRows) { results.Read(); foreach(DataRow result in dtenergy.Rows) { byte[] imgProd = result["ThumnailLocation"] as byte[]; ID.Text = result["ProductID"].ToString(); Name.Text = result["Name"].ToString(); price.Text = FormatPriceColumn(result["Price"].ToString()); } } Here is the code for the asp.net. <div> <asp:Image ID="imgProd" CssClass="ProdImg" runat="server" /> <asp:Label runat="server" ID="ID" /> <asp:Label runat="server" ID="Name" /> <asp:Label runat="server" ID="price" /> <asp:TextBox ID="txtQty" MaxLength="3" runat="server" Width="30px" /> <asp:Button runat="server" ID="Addtocart" Text="Add To Cart" CommandName="AddToCart" ItemStyle-CssClass="btnCol" /> If someone could please help me that would be great thanks.

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  • How do i find if an object is before or after a waypoint?

    - by BoMann Andersen
    Im working on a racing game for a school project. Using Visual studio 10 pro, and Irrlicht. Sorry for bad grammar ., and its my first question so not sure if its done right. How i want it to work is that i make waypoints at different points on the track, and then i run my waypoint check to see if a car is past its next waypoint (the next it "needs" to go past), if yes then it updates the next waypoint, else nothing. The way i hope this will work is, i make a vector from n to n+1, then find the vector that is perpendicular to the first vector at n. Then i see if the object is in front or behind that vector. I found a Gamedev.net forumpost that helped me make this function: void Engine::checkWaypoint(Vehicle* vehicle) { btVector3 vector = waypoints[vehicle->nextWaypoint]; // n btVector3 nextVector = waypoints[vehicle->nextWaypoint + 1]; // n+1 vector = nextVector - vector; // First vector btVector3 pos = btVector3(vehicle->position.X,vehicle->position.Y,vehicle->position.Z); float product = vector.dot(pos - waypoints[vehicle->nextWaypoint]); // positiv = before, negative = behind if(product < 0) vehicle->nextWaypoint += 1; } Current bugs with this is: Updates the nextwaypoint more then ones without going past a new point. When it gets to the end and resets, it stops triggering on the first waypoints. So my questions: Is this an good way to do this? Did i do it right?

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  • What is the fastest (to access) struct-like object in Python?

    - by DNS
    I'm optimizing some code whose main bottleneck is running through and accessing a very large list of struct-like objects. Currently I'm using namedtuples, for readability. But some quick benchmarking using 'timeit' shows that this is really the wrong way to go where performance is a factor: Named tuple with a, b, c: >>> timeit("z = a.c", "from __main__ import a") 0.38655471766332994 Class using __slots__, with a, b, c: >>> timeit("z = b.c", "from __main__ import b") 0.14527461047146062 Dictionary with keys a, b, c: >>> timeit("z = c['c']", "from __main__ import c") 0.11588272541098377 Tuple with three values, using a constant key: >>> timeit("z = d[2]", "from __main__ import d") 0.11106188992948773 List with three values, using a constant key: >>> timeit("z = e[2]", "from __main__ import e") 0.086038238242508669 Tuple with three values, using a local key: >>> timeit("z = d[key]", "from __main__ import d, key") 0.11187358437882722 List with three values, using a local key: >>> timeit("z = e[key]", "from __main__ import e, key") 0.088604143037173344 First of all, is there anything about these little timeit tests that would render them invalid? I ran each several times, to make sure no random system event had thrown them off, and the results were almost identical. It would appear that dictionaries offer the best balance between performance and readability, with classes coming in second. This is unfortunate, since, for my purposes, I also need the object to be sequence-like; hence my choice of namedtuple. Lists are substantially faster, but constant keys are unmaintainable; I'd have to create a bunch of index-constants, i.e. KEY_1 = 1, KEY_2 = 2, etc. which is also not ideal. Am I stuck with these choices, or is there an alternative that I've missed?

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  • SFINAE and detecting if a C++ function object returns void.

    - by Tom Swirly
    I've read the various authorities on this, include Dewhurst and yet haven't managed to get anywhere with this seemingly simple question. What I want to do is to call a C++ function object, (basically, anything you can call, a pure function or a class with ()), and return its value, if that is not void, or "true" otherwise. #include <stdio.h> struct Foo { void operator()() {} }; struct Bar { bool operator()() { return false; } }; Foo foo; Bar bar; bool baz() { return false; } void bang() {} const char* print(bool b) { printf(b ? "true, " : "false, "); } template <typename Functor> bool magicCallFunction(Functor f) { return true; // lots of template magic occurs here... } int main(int argc, char** argv) { print(magicCallFunction(foo)); print(magicCallFunction(bar)); print(magicCallFunction(baz)); print(magicCallFunction(bang)); printf("\n"); }

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  • how do I copy value from one table and inserted to another in the same database??

    - by mathew
    I am having a tough time to do this... I have created two table say table-1 and table-2 in same database.what I want is I need to copy some values from table-1 and insert the same to table-2. I have tried many ways but it does not seems work. below is my code can any one tell me where I am missing?? $db = mysql_connect("localhost", "user", "pass") or die("Could not connect."); mysql_select_db("comdata",$db)or die(mysql_error()); $resultb = mysql_query("SELECT * FROM table-2")or die(mysql_error()); $row = mysql_fetch_array($resultb); $days = (strtotime(date("Y-m-d")) - strtotime($row['regtime'])) / (60 * 60 * 24); if($row > 0 && $days < 1){ $person = $row['person']; $catogr = $row['catog']; $position = $row['position']; $location = $row['location']; $rank = $row['rank']; mysql_close($db); }else{ $db = mysql_connect("localhost", "user", "pass") or die("Could not connect."); mysql_select_db("comdata",$db)or die(mysql_error()); $result = mysql_query("SELECT * FROM table-1 WHERE regtime = DATE(NOW()) ORDER BY rank ASC LIMIT 1;")or die(mysql_error()); $row = mysql_fetch_array($result); $person = $row['person']; $catogr = $row['catog']; $position = $row['position']; $location = $row['location']; $rank = $row['rank']; mysql_query("INSERT INTO table-2 (regtime,person,catog,position,location,rank) VALUES(NOW(),'$person','$catogr','$position','$location','$rank')"); mysql_close($db); }

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  • How do I assign a rotating category to database entries in the order the records come in?

    - by Stomped
    I have a table which gets entries from a website, and as those entries go into the database, they need to be assigned the next category on a list of categories that may be changed at any time. Because of this reason I can't do something simple like for mapping the first category of 5 to IDs 1, 6, 11, 16. I've considered reading in the list of currently possibly categories, and checking the value of the last one inserted, and then giving the new record the next category, but I imagine if two requests come in at the same moment, I could potentially assign them both the same category rather then in sequence. So, my current round of thinking is the following: lock the tables ( categories and records ) insert the newest row into records get the newest row's ID select the row previous to the insertl ( by using order by auto_inc_name desc 0, 1 ) take the previous row's category, and grab the next one from the cat list update the new inserted row unlock the table I'm not 100% sure this will work right, and there's possibly a much easier way to do it, so I'm asking: A. Will this work as I described in the original problem? B. Do you have a better/easier way to do this? Thanks ~

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  • how to insert excel-2003 values into SQL2005 database?

    - by vas
    Are there any rules / guidelines for DATA form XLS sheets to be inserted into SQL- DB? I have a group of Excel templates in 2005.Each concerned cell in Excel template is named. When Excel sheets are filled, saved and submitted , the values are transferred to the database. Excel sheets have names for various cells that are to b e filled by the user EX:- for the total number of Milk in the Beginning a given month , there is an Excel Cell Named "mtsBpiPTR180" Total number of Milk in the Ending a given month , there is an Excel Cell Named **"mtsEpiPTR180"** I have added 2 new cells , named "mtsBpiPTR180PA" and "mtsEpiPTR180PA". Now I try to upload the Excel File. But I AM UNABLE TO SEE MY FILLED DATA FROM "mtsBpiPTR180PA" and "mtsEpiPTR180PA" INTO THE RELATED DB/table. The above 2 are empty in the DB/table, even though I have filled them and successfully filed the Excel sheets Now no matter how much I search in the DB/stored procs i am unable to the ACTUAL STORED PROC or how the Data form Excel sheet is inserted into Tables WHERE DATA FROM XLS is inserted into DB. So was wondering:- Are there any rules / guidelines for DATA form XLS sheets to be inserted into SQL- DB?

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  • Efficient batch SQL query execution on Android, for upgrade database.

    - by Pentium10
    As we Android developers know, the SQLiteDatabase execSQL method can execute only one statement. The doc says: Execute a single SQL statement that is not a query. For example, CREATE TABLE, DELETE, INSERT, etc. Multiple statements separated by ;s are not supported. I have to load in a batch of records, 1000 and counting. How do I insert these efficiently? And what's the easiest way to deliver these SQLs with your apk? I mention, there is already a system database and I will run this on the onUpdate event. I have this code so far: List<String[]> li = new ArrayList<String[]>(); li.add(new String[] { "-1", "Stop", "0" }); li.add(new String[] { "0", "Start", "0" }); /* the rest of the assign */ try { for (String[] elem : li) { getDb().execSQL( "INSERT INTO " + TABLENAME + " (" + _ID + "," + NAME + "," + PARSE_ORDER + ") VALUES (?,?,?)", elem); } } catch (Exception e) { e.printStackTrace(); }

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  • What happens when you create an instance of an object containing no state in C#?

    - by liquorice
    I am I think ok at algorithmic programming, if that is the right term? I used to play with turbo pascal and 8086 assembly language back in the 1980s as a hobby. But only very small projects and I haven't really done any programming in the 20ish years since then. So I am struggling for understanding like a drowning swimmer. So maybe this is a very niave question or I'm just making no sense at all, but say I have an object kind of like this: class Something : IDoer { void Do(ISomethingElse x) { x.DoWhatEverYouWant(42); } } And then I do var Thing1 = new Something(); var Thing2 = new Something(); Thing1.Do(blah); Thing2.Do(blah); does Thing1 = Thing2? does "new Something()" create anything? Or is it not much different different from having a static class, except I can pass it around and swap it out etc. Is the "Do" procedure in the same location in memory for both the Thing1(blah) and Thing2(blah) objects? I mean when executing it, does it mean there are two Something.Do procedures or just one?

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